Document and Entity Information Document - shares	6 Months Ended
Document and Entity Information Document - shares	Jun. 30, 2017	Aug. 02, 2017
Document Information [Line Items]
Entity Registrant Name	AMERICAN EQUITY INVESTMENT LIFE HOLDING CO
Entity Central Index Key	0001039828
Document Type	10-Q
Document Period End Date	Jun. 30, 2017
Amendment Flag	false
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		88,917,403

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Fixed maturity securities:
Available for sale, at fair value (amortized cost: 2017 - $41,907,744; 2016 - $39,953,955)	$ 43,893,785	$ 41,060,494
Held for investment, at amortized cost (fair value: 2017 - $76,702; 2016 - $68,766)	76,931	76,825
Mortgage loans on real estate	2,553,391	2,480,956
Derivative instruments	1,086,624	830,519
Other investments	314,421	308,774
Total investments	47,925,152	44,757,568
Cash and cash equivalents	1,574,913	791,266
Coinsurance deposits	4,710,650	4,639,492
Accrued investment income	416,482	397,773
Deferred policy acquisition costs	2,721,596	2,905,377
Deferred sales inducements	2,042,889	2,208,218
Deferred income taxes	64,074	168,578
Income taxes recoverable	952	11,474
Other assets	178,882	173,726
Total assets	59,635,590	56,053,472
Liabilities:
Policy benefit reserves	53,903,497	51,637,026
Other policy funds and contract claims	287,381	298,347
Notes and loan payable	888,660	493,755
Subordinated debentures	242,045	241,853
Amounts due under repurchase agreements	61,673	0
Other liabilities	1,600,926	1,090,896
Total liabilities	56,984,182	53,761,877
Stockholders' equity:
Preferred stock, par value $1 per share, 2,000,000 shares authorized, 2017 and 2016 - no shares issued and outstanding	0	0
Common stock, par value $1 per share, 200,000,000 shares authorized; issued and outstanding: 2017 - 88,741,014 shares (excluding 2,573,000 treasury shares); 2016 - 88,001,130 shares (excluding 2,887,082 treasury shares)	88,741	88,001
Additional paid-in capital	778,376	770,344
Accumulated other comprehensive income	610,122	339,966
Retained earnings	1,174,169	1,093,284
Total stockholders' equity	2,651,408	2,291,595
Total liabilities and stockholders' equity	$ 59,635,590	$ 56,053,472

Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Fixed maturity securities:
Available for sale, at fair value, amortized cost	$ 41,907,744	$ 39,953,955
Held for investment, at amortized cost, fair value	$ 76,702	$ 68,766
Stockholders' equity:
Preferred stock, par value (dollars per share)	$ 1	$ 1
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (dollars per share)	$ 1	$ 1
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	88,741,014	88,001,130
Common stock, shares outstanding	88,741,014	88,001,130
Common stock, shares held in treasury	2,573,000	2,887,082

Consolidated Statements of Operations - USD ($)
$ in Thousands

3 Months Ended

6 Months Ended

Jun. 30, 2017

Jun. 30, 2016

Jun. 30, 2017

Jun. 30, 2016

Revenues:

Premiums and other considerations

$ 7,720

$ 11,458

$ 17,122

$ 18,803

Annuity product charges

48,603

41,124

92,175

77,629

Net investment income

493,489

459,830

979,086

910,656

Change in fair value of derivatives

266,820

39,099

653,353

(34,966)

Net realized gains on investments, excluding other than temporary impairment (OTTI) losses

3,873

2,737

6,211

5,424

OTTI losses on investments:

Total OTTI losses

(762)

(6,780)

Portion of OTTI losses recognized from other comprehensive income

(949)

(3,684)

(1,090)

(3,360)

Net OTTI losses recognized in operations

(949)

(4,446)

(1,090)

(10,140)

Loss on extinguishment of debt

(428)

Total revenues

819,128

549,802

1,746,429

967,406

Benefits and expenses:

Insurance policy benefits and change in future policy benefits

9,986

13,393

21,861

22,502

Interest sensitive and index product benefits

472,596

111,121

891,735

208,792

Amortization of deferred sales inducements

33,695

30,672

96,020

58,151

Change in fair value of embedded derivatives

174,973

284,303

399,143

550,160

Interest expense on notes and loan payable

8,678

6,882

16,400

13,762

Interest expense on subordinated debentures

3,422

3,206

6,758

6,374

Amortization of deferred policy acquisition costs

49,547

50,665

139,225

100,378

Other operating costs and expenses

25,964

26,823

53,543

53,653

Total benefits and expenses

778,861

527,065

1,624,685

1,013,772

Income (loss) before income taxes

40,267

22,737

121,744

(46,366)

Income tax expense (benefit)

13,321

8,029

40,859

(16,233)

Net income (loss)

$ 26,946

$ 14,708

$ 80,885

$ (30,133)

Earnings (loss) per common share

$ 0.30

$ 0.18

$ 0.91

$ (0.37)

Earnings (loss) per common share - assuming dilution

$ 0.30

$ 0.18

$ 0.90

$ (0.37)

Weighted average common shares outstanding: earnings (loss) per common share

^[1]

88,897,203

82,516,927

88,772,831

82,322,919

Weighted average common shares outstanding: earnings (loss) per common share - assuming dilution

90,112,284

83,184,137

90,044,639

83,072,816

[1]	Weighted average common shares outstanding include shares vested under the NMO Deferred Compensation Plan.

Consolidated Statements of Comprehensive Income - USD ($)
$ in Thousands

3 Months Ended

6 Months Ended

Jun. 30, 2017

Jun. 30, 2016

Jun. 30, 2017

Jun. 30, 2016

Net income (loss)

$ 26,946

$ 14,708

$ 80,885

$ (30,133)

Other comprehensive income:

Change in net unrealized investment gains/losses (1)

^[1]

283,345

555,412

412,469

1,060,760

Noncredit component of OTTI losses (1)

^[1]

450

1,713

515

1,566

Reclassification of unrealized investment gains/losses to net income (loss) (1)

^[1]

1,711

1,511

2,641

1,627

Other comprehensive income before income tax

285,506

558,636

415,625

1,063,953

Income tax effect related to other comprehensive income

(99,927)

(195,523)

(145,469)

(372,384)

Other comprehensive income

185,579

363,113

270,156

691,569

Comprehensive income

$ 212,525

$ 377,821

$ 351,041

$ 661,436

[1]	Net of related adjustments to amortization of deferred sales inducements and deferred policy acquisition costs.

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income [Member]	Retained Earnings [Member]
Stockholders' equity at beginning of period at Dec. 31, 2015	$ 1,944,535	$ 81,354	$ 630,367	$ 201,663	$ 1,031,151
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(30,133)				(30,133)
Other comprehensive income	691,569			691,569
Share-based compensation	3,889		3,889
Issuance of common stock under compensation plans	3,531	832	2,699
Issuance of common stock to settle warrants that have reached their expiration	(1)	93	(94)
Stockholders' equity at end of period at Jun. 30, 2016	2,613,390	82,279	636,861	893,232	1,001,018
Stockholders' equity at beginning of period at Dec. 31, 2016	2,291,595	88,001	770,344	339,966	1,093,284
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	80,885				80,885
Other comprehensive income	270,156			270,156
Share-based compensation	4,154		4,154
Issuance of common stock under compensation plans	4,618	740	3,878
Stockholders' equity at end of period at Jun. 30, 2017	$ 2,651,408	$ 88,741	$ 778,376	$ 610,122	$ 1,174,169

Consolidated Statements of Changes in Stockholders' Equity (Parentheticals) - shares	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Shares of common stock issued under compensation plans	739,884	831,694
Shares of common stock issued to settle warrants that have reached their expiration		92,998

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Operating activities
Net income (loss)	$ 80,885	$ (30,133)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Interest sensitive and index product benefits	891,735	208,792
Amortization of deferred sales inducements	96,020	58,151
Annuity product charges	(92,175)	(77,629)
Change in fair value of embedded derivatives	399,143	550,160
Change in traditional life and accident and health insurance reserves	122	2,261
Policy acquisition costs deferred	(221,909)	(304,877)
Amortization of deferred policy acquisition costs	139,225	100,378
Provision for depreciation and other amortization	1,961	1,745
Amortization of discounts and premiums on investments	8,644	(5,342)
Realized gains (losses) on investments and net OTTI losses recognized in operations	(5,121)	4,716
Change in fair value of derivatives	(653,939)	34,172
Deferred income taxes	(40,965)	(40,257)
Loss on extinguishment of debt	428	0
Share-based compensation	4,154	3,448
Change in accrued investment income	(18,709)	(15,289)
Change in income taxes recoverable/payable	10,522	(6,078)
Change in other assets	433	706
Change in other policy funds and contract claims	(14,824)	(23,793)
Change in collateral held for derivatives	289,258	10,615
Change in other liabilities	(36,848)	(41,573)
Other	(6,960)	(7,793)
Net cash provided by operating activities	831,080	422,380
Sales, maturities, or repayments of investments:
Fixed maturity securities - available for sale	970,752	1,421,976
Mortgage loans on real estate	185,406	215,904
Derivative instruments	750,345	15,859
Other investments	7,511	11,597
Acquisitions of investments:
Fixed maturity securities - available for sale	(2,680,972)	(2,542,281)
Mortgage loans on real estate	(257,050)	(229,328)
Derivative instruments	(320,583)	(289,412)
Other investments	(6,950)	(6,945)
Purchases of property, furniture and equipment	(2,494)	(506)
Net cash used in investing activities	(1,354,035)	(1,403,136)
Financing activities
Receipts credited to annuity and single premium universal life policyholder account balances	2,243,180	4,181,709
Coinsurance deposits	30,938	(884,741)
Return of annuity policyholder account balances	(1,401,086)	(1,168,302)
Financing fees incurred and deferred	(5,823)	0
Proceeds from issuance of notes payable	499,650	0
Repayment of debt	(100,000)	0
Net proceeds from amounts due under repurchase agreements	61,673	0
Excess tax benefits realized from share-based compensation plans	0	441
Proceeds from issuance of common stock	4,618	3,779
Change in checks in excess of cash balance	(26,548)	(2,838)
Net cash provided by financing activities	1,306,602	2,130,048
Increase in cash and cash equivalents	783,647	1,149,292
Cash and cash equivalents at beginning of period	791,266	397,749
Cash and cash equivalents at end of period	1,574,913	1,547,041
Cash paid during period for interest:
Interest expense	22,739	19,390
Cash paid during period for income taxes:
Income taxes	71,526	29,961
Non-cash operating activity:
Deferral of sales inducements	128,092	196,207
Non-cash financing activity:
Common stock issued to settle warrants that have expired	$ 0	$ 93

Significant Accounting Policies	6 Months Ended
Significant Accounting Policies	Jun. 30, 2017
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Consolidation and Basis of Presentation The accompanying consolidated financial statements of American Equity Investment Life Holding Company (“we”, “us” or “our”) have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all the information and notes required by GAAP for complete financial statements. The consolidated financial statements reflect all adjustments, consisting only of normal recurring items, which are necessary to present fairly our financial position and results of operations on a basis consistent with the prior audited consolidated financial statements. Operating results for the three and six month periods ended June 30, 2017 are not necessarily indicative of the results that may be expected for the year ended December 31, 2017. All significant intercompany accounts and transactions have been eliminated. The preparation of financial statements requires the use of management estimates. For further information related to a description of areas of judgment and estimates and other information necessary to understand our financial position and results of operations, refer to the audited consolidated financial statements and notes included in our Annual Report on Form 10-K for the year ended December 31, 2016. Adopted Accounting Pronouncements In March 2016, the Financial Accounting Standards Board ("FASB") issued an accounting standards update ("ASU") related to the accounting for share-based payment transactions. The aspects of accounting guidance affected by this ASU are income taxes, classification of awards as either equity or liabilities, and classification on the statement of cash flows. We adopted this ASU on January 1, 2017. The adoption of this ASU resulted in an income tax benefit of $0.3 million and $1.6 million being recognized in operations during the three and six month periods ended June 30, 2017 due to the requirement under this standard to recognize excess tax benefits related to share-based payment awards in income tax expense. New Accounting Pronouncements In January 2016, the FASB issued an ASU that, among other aspects of recognition, measurement, presentation and disclosure of financial instruments, primarily requires equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income. However, an entity may choose to measure equity investments that do not have readily determinable fair values at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. Additionally, it changes the accounting for financial liabilities measured at fair value under the fair value option and eliminates some disclosures regarding fair value of financial assets and liabilities measured at amortized cost. This ASU will be effective for us on January 1, 2018, and we have not determined the effect it will have on our consolidated financial statements. In February 2016, the FASB issued an ASU that will require recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. This ASU affects accounting and disclosure more dramatically for lessees as accounting for lessors is mainly unchanged. This ASU will be effective for us on January 1, 2019, with early adoption permitted, and we have not determined the effect it will have on our consolidated financial statements. In June 2016, the FASB issued an ASU that significantly changes the impairment model for most financial assets that are measured at amortized cost and certain other instruments from an incurred loss model to an expected loss model that requires these assets be presented at the net amount expected to be collected. In addition, credit losses on available for sale debt securities should be recorded through an allowance account. This ASU will be effective for us on January 1, 2020, with early adoption permitted, and we have not yet determined the impact this updated guidance will have on our consolidated financial statements. In August 2016, the FASB issued an ASU that clarifies how certain cash receipts and cash payments are to be presented and classified in the statement of cash flows. This ASU will be effective for us on January 1, 2018, with early adoption permitted, and we have not yet determined the impact this updated guidance will have on our consolidated financial statements. In March 2017, the FASB issued an ASU that applies to certain callable debt securities where the amortized cost basis is at a premium to the price repayable by the issuer at the earliest call date. Under this guidance, the premium will be amortized to the first call date. This ASU will be effective for us on January 1, 2019, with early adoption permitted, and we have not yet determined the impact this updated guidance will have on our consolidated financial statements.

Fair Values of Financial Instruments

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Fair Values of Financial Instruments

The following sets forth a comparison of the carrying amounts and fair values of our financial instruments:



	June 30, 2017				December 31, 2016
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
	(Dollars in thousands)
Assets
Fixed maturity securities:
Available for sale	$	43,893,785	$	43,893,785	$	41,060,494	$	41,060,494
Held for investment	76,931		76,702		76,825		68,766
Mortgage loans on real estate	2,553,391		2,554,995		2,480,956		2,522,035
Derivative instruments	1,086,624		1,086,624		830,519		830,519
Other investments	314,421		305,551		308,774		300,918
Cash and cash equivalents	1,574,913		1,574,913		791,266		791,266
Coinsurance deposits	4,710,650		4,213,996		4,639,492		4,150,792
Interest rate caps	468		468		1,082		1,082
Counterparty collateral	144,283		144,283		145,693		145,693

Liabilities
Policy benefit reserves	53,546,680		44,785,605		51,280,331		43,104,183
Single premium immediate annuity (SPIA) benefit reserves	286,856		296,948		297,724		308,028
Notes and loan payable	888,660		929,437		493,755		519,440
Subordinated debentures	242,045		245,190		241,853		225,106
Amounts due under repurchase agreements	61,673		61,673		—		—
Interest rate swap	2,001		2,001		2,113		2,113

Fair value is the price that would be received to sell an asset or paid to transfer a liability (exit price) in an orderly transaction between market participants at the measurement date. The objective of a fair value measurement is to determine that price for each financial instrument at each measurement date. We meet this objective using various methods of valuation that include market, income and cost approaches.

We categorize our financial instruments into three levels of fair value hierarchy based on the priority of inputs used in determining fair value. The hierarchy defines the highest priority inputs (Level 1) as quoted prices in active markets for identical assets or liabilities. The lowest priority inputs (Level 3) are our own assumptions about what a market participant would use in determining fair value such as estimated future cash flows. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, a financial instrument's level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. Our assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the financial instrument. We categorize financial assets and liabilities recorded at fair value in the consolidated balance sheets as follows:


Level 1—	Quoted prices are available in active markets for identical financial instruments as of the reporting date. We do not adjust the quoted price for these financial instruments, even in situations where we hold a large position and a sale could reasonably impact the quoted price.


Level 2—	Quoted prices in active markets for similar financial instruments, quoted prices for identical or similar financial instruments in markets that are not active; and models and other valuation methodologies using inputs other than quoted prices that are observable.

Level 3—

Models and other valuation methodologies using significant inputs that are unobservable for financial instruments and include situations where there is little, if any, market activity for the financial instrument. The inputs into the determination of fair value require significant management judgment or estimation. Financial instruments that are included in Level 3 are securities for which no market activity or data exists and for which we used discounted expected future cash flows with our own assumptions about what a market participant would use in determining fair value.

Transfers of securities among the levels occur at times and depend on the type of inputs used to determine fair value of each security. There were no transfers between levels during any period presented.

Our assets and liabilities which are measured at fair value on a recurring basis as of June 30, 2017 and December 31, 2016 are presented below based on the fair value hierarchy levels:



	Total Fair Value		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(Dollars in thousands)
June 30, 2017
Assets
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	12,174	$	5,807	$	6,367	$	—
United States Government sponsored agencies	1,340,839		—		1,340,839		—
United States municipalities, states and territories	4,137,714		—		4,137,714		—
Foreign government obligations	238,869		—		238,869		—
Corporate securities	29,287,071		6		29,287,065		—
Residential mortgage backed securities	1,181,850		—		1,181,850		—
Commercial mortgage backed securities	5,540,383		—		5,540,383		—
Other asset backed securities	2,154,885		—		2,154,885		—
Other investments: equity securities, available for sale	7,982		—		7,982		—
Derivative instruments	1,086,624		—		1,086,624		—
Cash and cash equivalents	1,574,913		1,574,913		—		—
Interest rate caps	468		—		468		—
Counterparty collateral	144,283		—		144,283		—
	$	46,708,055	$	1,580,726	$	45,127,329	$	—
Liabilities
Interest rate swap	$	2,001	$	—	$	2,001	$	—
Fixed index annuities - embedded derivatives	7,552,365		—		—		7,552,365
	$	7,554,366	$	—	$	2,001	$	7,552,365

December 31, 2016
Assets
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	11,805	$	5,381	$	6,424	$	—
United States Government sponsored agencies	1,344,787		—		1,344,787		—
United States municipalities, states and territories	3,926,950		—		3,926,950		—
Foreign government obligations	236,341		—		236,341		—
Corporate securities	27,114,418		6		27,114,412		—
Residential mortgage backed securities	1,254,835		—		1,254,835		—
Commercial mortgage backed securities	5,365,235		—		5,365,235		—
Other asset backed securities	1,806,123		—		1,806,123		—
Other investments: equity securities, available for sale	8,000		—		8,000		—
Derivative instruments	830,519		—		830,519		—
Cash and cash equivalents	791,266		791,266		—		—
Interest rate caps	1,082		—		1,082		—
Counterparty collateral	145,693		—		145,693		—
	$	42,837,054	$	796,653	$	42,040,401	$	—
Liabilities
Interest rate swap	$	2,113	$	—	$	2,113	$	—
Fixed index annuities - embedded derivatives	6,563,288		—		—		6,563,288
	$	6,565,401	$	—	$	2,113	$	6,563,288

The following methods and assumptions were used in estimating the fair values of financial instruments during the periods presented in these consolidated financial statements.

Fixed maturity securities and equity securities

The fair values of fixed maturity securities and equity securities in an active and orderly market are determined by utilizing independent pricing services. The independent pricing services incorporate a variety of observable market data in their valuation techniques, including:


•	reported trading prices,


•	benchmark yields,


•	broker-dealer quotes,


•	benchmark securities,


•	bids and offers,


•	credit ratings,


•	relative credit information, and


•	other reference data.

The independent pricing services also take into account perceived market movements and sector news, as well as a security's terms and conditions, including any features specific to that issue that may influence risk and marketability. Depending on the security, the priority of the use of observable market inputs may change as some observable market inputs may not be relevant or additional inputs may be necessary.

The independent pricing services provide quoted market prices when available. Quoted prices are not always available due to market inactivity. When quoted market prices are not available, the third parties use yield data and other factors relating to instruments or securities with similar characteristics to determine fair value for securities that are not actively traded. We generally obtain one value from our primary external pricing service. In situations where a price is not available from this service, we may obtain quotes or prices from additional parties as needed. In addition, for our callable United States Government sponsored agencies, we obtain multiple broker quotes and take the average of the broker prices received. Market indices of similar rated asset class spreads are considered for valuations and broker indications of similar securities are compared. Inputs used by the broker include market information, such as yield data and other factors relating to instruments or securities with similar characteristics. Valuations and quotes obtained from third party commercial pricing services are non-binding and do not represent quotes on which one may execute the disposition of the assets.

We validate external valuations at least quarterly through a combination of procedures that include the evaluation of methodologies used by the pricing services, analytical reviews and performance analysis of the prices against trends, and maintenance of a securities watch list. Additionally, as needed we utilize discounted cash flow models or perform independent valuations on a case-by-case basis using inputs and assumptions similar to those used by the pricing services. Although we do identify differences from time to time as a result of these validation procedures, we did not make any significant adjustments as of June 30, 2017 and December 31, 2016.

Mortgage loans on real estate

Mortgage loans on real estate are not measured at fair value on a recurring basis. The fair values of mortgage loans on real estate are calculated using discounted expected cash flows using current competitive market interest rates currently being offered for similar loans. The fair values of impaired mortgage loans on real estate that we have considered to be collateral dependent are based on the fair value of the real estate collateral (based on appraised values) less estimated costs to sell. The inputs utilized to determine fair value of all mortgage loans are unobservable market data (competitive market interest rates); therefore, fair value of mortgage loans falls into Level 3 in the fair value hierarchy.

Derivative instruments

The fair values of derivative instruments, primarily call options, are based upon the amount of cash that we will receive to settle each derivative instrument on the reporting date. These amounts are determined by our investment team using industry accepted valuation models and are adjusted for the nonperformance risk of each counterparty net of any collateral held. Inputs include market volatility and risk free interest rates and are used in income valuation techniques in arriving at a fair value for each option contract. The nonperformance risk for each counterparty is based upon its credit default swap rate. We have no performance obligations related to the call options purchased to fund our fixed index annuity policy liabilities.

Other investments

Available for sale equity securities are the only financial instruments included in other investments that are measured at fair value on a recurring basis (see determination of fair value above). Financial instruments included in other investments that are not measured at fair value on a recurring basis are policy loans, equity method investments and company owned life insurance (COLI). We have not attempted to determine the fair values associated with our policy loans, as we believe any differences between carrying value and the fair values afforded these instruments are immaterial to our consolidated financial position and, accordingly, the cost to provide such disclosure does not justify the benefit to be derived. The fair value of our equity method investments qualify as Level 3 fair values and were determined by calculating the present value of future cash flows discounted by a risk free rate, a risk spread and a liquidity discount. The risk spread and liquidity discount are rates determined by our investment professionals and are unobservable market inputs. The fair value of our COLI approximates the cash surrender value of the policies and whose fair values fall within Level 2 of the fair value hierarchy.

Cash and cash equivalents

Amounts reported in the consolidated balance sheets for these instruments are reported at their historical cost which approximates fair value due to the nature of the assets assigned to this category.

Interest rate swap and caps

The fair values of our pay fixed/receive variable interest rate swap and our interest rate caps are obtained from third parties and are determined by discounting expected future cash flows using projected LIBOR rates for the term of the swap and caps.

Counterparty collateral

Amounts reported in other assets in the consolidated balance sheets for these instruments are reported at their historical cost which approximates fair value due to the nature of the assets assigned to this category.

Policy benefit reserves, coinsurance deposits and SPIA benefit reserves

The fair values of the liabilities under contracts not involving significant mortality or morbidity risks (principally deferred annuities), are stated at the cost we would incur to extinguish the liability (i.e., the cash surrender value) as these contracts are generally issued without an annuitization date. The coinsurance deposits related to the annuity benefit reserves have fair values determined in a similar fashion. For period-certain annuity benefit contracts, the fair value is determined by discounting the benefits at the interest rates currently in effect for newly issued immediate annuity contracts. We are not required to and have not estimated the fair value of the liabilities under contracts that involve significant mortality or morbidity risks, as these liabilities fall within the definition of insurance contracts that are exceptions from financial instruments that require disclosures of fair value. Policy benefit reserves, coinsurance deposits and SPIA benefit reserves are not measured at fair value on a recurring basis. All of the fair values presented within these categories fall within Level 3 of the fair value hierarchy as most of the inputs are unobservable market data.

Notes and loan payable

The fair values of our senior unsecured notes are based upon pricing matrices developed by a third party pricing service when quoted market prices are not available and are categorized as Level 2 within the fair value hierarchy. The fair value of our term loan is estimated using discounted cash flow calculations based principally on observable inputs including our incremental borrowing rate, which reflects our credit rating, for a similar type of borrowing with a maturity consistent with that remaining for the term loan. Notes and loan payable are not remeasured at fair value on a recurring basis.

Subordinated debentures

Fair values for subordinated debentures are estimated using discounted cash flow calculations based principally on observable inputs including our incremental borrowing rates, which reflect our credit rating, for similar types of borrowings with maturities consistent with those remaining for the debt being valued. These fair values are categorized as Level 2 within the fair value hierarchy. Subordinated debentures are not measured at fair value on a recurring basis.

Amounts due under repurchase agreements

The amounts reported in the consolidated balance sheets for short term indebtedness under repurchase agreements with variable interest rates approximate their fair values.

Fixed index annuities - embedded derivatives

We estimate the fair value of the embedded derivative component of our fixed index annuity policy benefit reserves at each valuation date by (i) projecting policy contract values and minimum guaranteed contract values over the expected lives of the contracts and (ii) discounting the excess of the projected contract value amounts at the applicable risk free interest rates adjusted for our nonperformance risk related to those liabilities. The projections of policy contract values are based on our best estimate assumptions for future policy growth and future policy decrements. Our best estimate assumptions for future policy growth include assumptions for the expected index credit on the next policy anniversary date which are derived from the fair values of the underlying call options purchased to fund such index credits and the expected costs of annual call options we will purchase in the future to fund index credits beyond the next policy anniversary. The projections of minimum guaranteed contract values include the same best estimate assumptions for policy decrements as were used to project policy contract values.

Within this determination we have the following significant unobservable inputs: 1) the expected cost of annual call options we will purchase in the future to fund index credits beyond the next policy anniversary and 2) our best estimates for future policy decrements, primarily lapse, partial withdrawal and mortality rates. As of June 30, 2017 and December 31, 2016, we utilized an estimate of 3.10% for the expected cost of annual call options, which are based on estimated long-term account value growth and a historical review of our actual option costs.

Our best estimate assumptions for lapse, partial withdrawal and mortality rates are based on our actual experience and our outlook as to future expectations for such assumptions. These assumptions, which are consistent with the assumptions used in calculating deferred policy acquisition costs and deferred sales inducements, are reviewed on a quarterly basis and are revised as our experience develops and/or as future expectations change. Our mortality rate assumptions are based on 65% of the 1983 Basic Annuity Mortality Tables. The following table presents average lapse rate and partial withdrawal rate assumptions, by contract duration, used in estimating the fair value of the embedded derivative component of our fixed index annuity policy benefit reserves at each reporting date:



	Average Lapse Rates		Average Partial Withdrawal Rates
Contract Duration (Years)	June 30, 2017	December 31, 2016	June 30, 2017	December 31, 2016
1 - 5	1.95%	1.76%	3.31%	3.30%
6 - 10	6.85%	6.58%	3.32%	3.30%
11 - 15	11.28%	11.25%	3.33%	3.32%
16 - 20	11.99%	12.04%	3.19%	3.18%
20+	11.65%	11.68%	3.19%	3.18%

Lapse rates are generally expected to increase as surrender charge percentages decrease. Lapse expectations reflect a significant increase in the year in which the surrender charge period on a contract ends.

The following table provides a reconciliation of the beginning and ending balances for our Level 3 liabilities, which are measured at fair value on a recurring basis using significant unobservable inputs for the three and six months ended June 30, 2017 and 2016:



	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
	(Dollars in thousands)
Fixed index annuities - embedded derivatives
Beginning balance	$	7,051,000	$	6,254,466	$	6,563,288	$	5,983,622
Premiums less benefits	497,689		44,632		909,191		135,761
Change in fair value, net	3,676		199,917		79,886		379,632
Ending balance	$	7,552,365	$	6,499,015	$	7,552,365	$	6,499,015

Change in fair value, net for each period in our embedded derivatives are included in change in fair value of embedded derivatives in the unaudited consolidated statements of operations.

Certain derivatives embedded in our fixed index annuity contracts are our most significant financial instrument measured at fair value that are categorized as Level 3 in the fair value hierarchy. The contractual obligations for future annual index credits within our fixed index annuity contracts are treated as a "series of embedded derivatives" over the expected life of the applicable contracts. We estimate the fair value of these embedded derivatives at each valuation date by the method described above under fixed index annuities - embedded derivatives. The projections of minimum guaranteed contract values include the same best estimate assumptions for policy decrements as were used to project policy contract values.

The most sensitive assumption in determining policy liabilities for fixed index annuities is the rates used to discount the excess projected contract values. As indicated above, the discount rate reflects our nonperformance risk. If the discount rates used to discount the excess projected contract values at June 30, 2017, were to increase by 100 basis points, the fair value of the embedded derivatives would decrease by $510.7 million recorded through operations as a decrease in the change in fair value of embedded derivatives and there would be a corresponding decrease of $307.0 million to our combined balance for deferred policy acquisition costs and deferred sales inducements recorded through operations as an increase in amortization of deferred policy acquisition costs and deferred sales inducements. A decrease by 100 basis points in the discount rate used to discount the excess projected contract values would increase the fair value of the embedded derivatives by $570.3 million recorded through operations as an increase in the change in fair value of embedded derivatives and there would be a corresponding increase of $337.7 million to our combined balance for deferred policy acquisition costs and deferred sales inducements recorded through operations as a decrease in amortization of deferred policy acquisition costs and deferred sales inducements.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Investments

6 Months Ended

Jun. 30, 2017

Investments [Abstract]

Investments

At June 30, 2017 and December 31, 2016, the amortized cost and fair value of fixed maturity securities were as follows:



	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(Dollars in thousands)
June 30, 2017
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	12,114	$	228	$	(168	)	$	12,174
United States Government sponsored agencies	1,348,391		30,288		(37,840		)	1,340,839
United States municipalities, states and territories	3,777,760		369,526		(9,572		)	4,137,714
Foreign government obligations	228,896		12,462		(2,489		)	238,869
Corporate securities	27,813,420		1,656,805		(183,154		)	29,287,071
Residential mortgage backed securities	1,090,846		93,316		(2,312		)	1,181,850
Commercial mortgage backed securities	5,519,767		89,865		(69,249		)	5,540,383
Other asset backed securities	2,116,550		51,796		(13,461		)	2,154,885
	$	41,907,744	$	2,304,286	$	(318,245	)	$	43,893,785
Held for investment:
Corporate security	$	76,931	$	—	$	(229	)	$	76,702

Other investments: equity securities, available for sale:
Finance, insurance, and real estate	$	7,525	$	457	$	—		$	7,982

December 31, 2016
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	11,864	$	229	$	(288	)	$	11,805
United States Government sponsored agencies	1,368,340		23,360		(46,913		)	1,344,787
United States municipalities, states and territories	3,626,395		322,948		(22,393		)	3,926,950
Foreign government obligations	229,589		11,832		(5,080		)	236,341
Corporate securities	26,333,213		1,149,978		(368,773		)	27,114,418
Residential mortgage backed securities	1,166,944		91,445		(3,554		)	1,254,835
Commercial mortgage backed securities	5,422,255		59,994		(117,014		)	5,365,235
Other asset backed securities	1,795,355		31,471		(20,703		)	1,806,123
	$	39,953,955	$	1,691,257	$	(584,718	)	$	41,060,494
Held for investment:
Corporate security	$	76,825	$	—	$	(8,059	)	$	68,766

Other investments: equity securities, available for sale:
Finance, insurance, and real estate	$	7,521	$	479	$	—		$	8,000

At June 30, 2017, 37% of our fixed income securities have call features, of which 2.1% ($899.1 million) were subject to call redemption and another 1.0% ($409.5 million) will become subject to call redemption during the next twelve months. Approximately 72% of our fixed income securities that have call features are not callable until within six months of their stated maturities.

The amortized cost and fair value of fixed maturity securities at June 30, 2017, by contractual maturity, are shown below. Actual maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. All of our mortgage and other asset backed securities provide for periodic payments throughout their lives and are shown below as separate lines.



	Available for sale				Held for investment
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
	(Dollars in thousands)
Due in one year or less	$	287,042	$	294,085	$	—	$	—
Due after one year through five years	3,482,397		3,645,145		—		—
Due after five years through ten years	11,828,053		12,116,887		—		—
Due after ten years through twenty years	8,981,750		9,715,165		—		—
Due after twenty years	8,601,339		9,245,385		76,931		76,702
	33,180,581		35,016,667		76,931		76,702
Residential mortgage backed securities	1,090,846		1,181,850		—		—
Commercial mortgage backed securities	5,519,767		5,540,383		—		—
Other asset backed securities	2,116,550		2,154,885		—		—
	$	41,907,744	$	43,893,785	$	76,931	$	76,702

Net unrealized gains on available for sale fixed maturity securities and equity securities reported as a separate component of stockholders' equity were comprised of the following:



	June 30, 2017			December 31, 2016
	(Dollars in thousands)
Net unrealized gains on available for sale fixed maturity securities and equity securities	$	1,986,498		$	1,107,018
Adjustments for assumed changes in amortization of deferred policy acquisition costs and deferred sales inducements	(1,082,516		)	(618,661		)
Deferred income tax valuation allowance reversal	22,534			22,534
Deferred income tax expense	(316,394		)	(170,925		)
Net unrealized gains reported as accumulated other comprehensive income	$	610,122		$	339,966

The National Association of Insurance Commissioners (“NAIC”) assigns designations to fixed maturity securities. These designations range from Class 1 (highest quality) to Class 6 (lowest quality). In general, securities are assigned a designation based upon the ratings they are given by the Nationally Recognized Statistical Rating Organizations (“NRSRO’s”). The NAIC designations are utilized by insurers in preparing their annual statutory statements. NAIC Class 1 and 2 designations are considered “investment grade” while NAIC Class 3 through 6 designations are considered “non-investment grade.” Based on the NAIC designations, we had 97% of our fixed maturity portfolio rated investment grade at both June 30, 2017 and December 31, 2016, respectively.

The following table summarizes the credit quality, as determined by NAIC designation, of our fixed maturity portfolio as of the dates indicated:



	June 30, 2017				December 31, 2016
NAIC Designation	Amortized Cost		Fair Value		Amortized Cost		Fair Value
	(Dollars in thousands)
1	$	26,718,443	$	28,144,706	$	25,607,268	$	26,507,798
2	13,907,192		14,499,548		13,037,592		13,295,648
3	1,229,695		1,207,581		1,201,059		1,155,702
4	97,349		89,144		154,226		137,188
5	19,559		20,698		17,475		24,664
6	12,437		8,810		13,160		8,260
	$	41,984,675	$	43,970,487	$	40,030,780	$	41,129,260

The following table shows our investments' gross unrealized losses and fair value, aggregated by investment category and length of time that individual securities (consisting of 956 and 1,514 securities, respectively) have been in a continuous unrealized loss position, at June 30, 2017 and December 31, 2016:



	Less than 12 months					12 months or more					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(Dollars in thousands)
June 30, 2017
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	6,867	$	(168	)	$	—	$	—		$	6,867	$	(168	)
United States Government sponsored agencies	945,126		(35,343		)	49,503		(2,497		)	994,629		(37,840		)
United States municipalities, states and territories	273,302		(9,572		)	—		—			273,302		(9,572		)
Foreign government obligations	—		—			11,844		(2,489		)	11,844		(2,489		)
Corporate securities:
Finance, insurance and real estate	1,132,134		(37,599		)	86,335		(1,495		)	1,218,469		(39,094		)
Manufacturing, construction and mining	458,458		(9,156		)	200,709		(13,648		)	659,167		(22,804		)
Utilities and related sectors	523,863		(14,319		)	43,553		(2,612		)	567,416		(16,931		)
Wholesale/retail trade	282,589		(9,583		)	42,120		(4,812		)	324,709		(14,395		)
Services, media and other	1,156,695		(33,573		)	619,260		(56,357		)	1,775,955		(89,930		)
Residential mortgage backed securities	40,684		(1,631		)	8,036		(681		)	48,720		(2,312		)
Commercial mortgage backed securities	1,924,949		(44,461		)	439,081		(24,788		)	2,364,030		(69,249		)
Other asset backed securities	528,570		(6,387		)	65,296		(7,074		)	593,866		(13,461		)
	$	7,273,237	$	(201,792	)	$	1,565,737	$	(116,453	)	$	8,838,974	$	(318,245	)
Held for investment:
Corporate security:
Insurance	$	—	$	—		$	76,702	$	(229	)	$	76,702	$	(229	)

December 31, 2016
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	7,405	$	(288	)	$	—	$	—		$	7,405	$	(288	)
United States Government sponsored agencies	995,548		(46,913		)	—		—			995,548		(46,913		)
United States municipalities, states and territories	463,409		(22,393		)	—		—			463,409		(22,393		)
Foreign government obligations	29,158		(913		)	20,388		(4,167		)	49,546		(5,080		)
Corporate securities:
Finance, insurance and real estate	1,940,107		(70,421		)	82,907		(7,723		)	2,023,014		(78,144		)
Manufacturing, construction and mining	1,199,420		(34,304		)	311,591		(23,273		)	1,511,011		(57,577		)
Utilities and related sectors	1,401,650		(45,015		)	58,597		(5,820		)	1,460,247		(50,835		)
Wholesale/retail trade	637,121		(18,880		)	29,719		(1,930		)	666,840		(20,810		)
Services, media and other	2,539,519		(82,196		)	716,857		(79,211		)	3,256,376		(161,407		)
Residential mortgage backed securities	81,762		(3,463		)	1,853		(91		)	83,615		(3,554		)
Commercial mortgage backed securities	3,148,395		(116,938		)	895		(76		)	3,149,290		(117,014		)
Other asset backed securities	751,533		(12,289		)	146,167		(8,414		)	897,700		(20,703		)
	$	13,195,027	$	(454,013	)	$	1,368,974	$	(130,705	)	$	14,564,001	$	(584,718	)
Held for investment:
Corporate security:
Insurance	$	—	$	—		$	68,766	$	(8,059	)	$	68,766	$	(8,059	)

Based on the results of our process for evaluating available for sale securities in unrealized loss positions for other than temporary impairments, which is discussed in detail later in this footnote, we have determined that the unrealized losses on the securities in the preceding table are temporary. The unrealized losses at June 30, 2017 are principally related to timing of the purchases of these securities, which carry less yield than those available at June 30, 2017.

Approximately 81% and 86% of the unrealized losses on fixed maturity securities shown in the above table for June 30, 2017 and December 31, 2016, respectively, are on securities that are rated investment grade, defined as being the highest two NAIC designations. All of the fixed maturity securities with unrealized losses are current with respect to the payment of principal and interest.

Changes in net unrealized gains on investments for the three and six months ended June 30, 2017 and 2016 are as follows:



	Three Months Ended June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
	(Dollars in thousands)
Fixed maturity securities held for investment carried at amortized cost	$	9,806		$	820		$	7,830		$	3,065
Investments carried at fair value:
Fixed maturity securities, available for sale	$	598,408		$	1,167,861		$	879,502		$	2,282,946
Equity securities, available for sale	(9		)	(1		)	(22		)	(18		)
	598,399			1,167,860			879,480			2,282,928
Adjustment for effect on other balance sheet accounts:
Deferred policy acquisition costs and deferred sales inducements	(312,893		)	(609,224		)	(463,855		)	(1,218,975		)
Deferred income tax asset/liability	(99,927		)	(195,523		)	(145,469		)	(372,384		)
	(412,820		)	(804,747		)	(609,324		)	(1,591,359		)
Change in net unrealized gains on investments carried at fair value	$	185,579		$	363,113		$	270,156		$	691,569

Proceeds from sales of available for sale securities for the six months ended June 30, 2017 and 2016 were $376.9 million and $186.1 million, respectively. Scheduled principal repayments, calls and tenders for available for sale securities for the six months ended June 30, 2017 and 2016 were $593.8 million and $1.2 billion, respectively.

Realized gains and losses on sales are determined on the basis of specific identification of investments based on the trade date. Net realized gains on investments, excluding net OTTI losses for the three and six months ended June 30, 2017 and 2016, are as follows:



	Three Months Ended June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
	(Dollars in thousands)
Available for sale fixed maturity securities:
Gross realized gains	$	4,479		$	4,604		$	10,051		$	6,091
Gross realized losses	(899		)	(1,368		)	(4,462		)	(2,599		)
	3,580			3,236			5,589			3,492
Other investments:
Gain on sale of real estate	15			705			44			836
Loss on sale of real estate	—			(1		)	—			(93		)
	15			704			44			743
Mortgage loans on real estate:
Decrease (increase) in allowance for credit losses	278			(2,885		)	578			(3,833		)
Recovery of specific allowance	—			1,682			—			5,022
	278			(1,203		)	578			1,189
	$	3,873		$	2,737		$	6,211		$	5,424

Losses on available for sale fixed maturity securities were realized primarily due to strategies to reposition the fixed maturity security portfolio that result in improved net investment income, credit risk or duration profiles as they pertain to our asset liability management. Securities were sold at losses in 2017 and 2016 due to our long-term fundamental concern with the issuers' ability to meet their future financial obligations.

We review and analyze all investments on an ongoing basis for changes in market interest rates and credit deterioration. This review process includes analyzing our ability to recover the amortized cost basis of each investment that has a fair value that is materially lower than its amortized cost and requires a high degree of management judgment and involves uncertainty. The evaluation of securities for other than temporary impairments is a quantitative and qualitative process, which is subject to risks and uncertainties.

We have a policy and process to identify securities that could potentially have impairments that are other than temporary. This process involves monitoring market events and other items that could impact issuers. The evaluation includes but is not limited to such factors as:


•	the length of time and the extent to which the fair value has been less than amortized cost or cost;


•	whether the issuer is current on all payments and all contractual payments have been made as agreed;


•	the remaining payment terms and the financial condition and near-term prospects of the issuer;


•	the lack of ability to refinance due to liquidity problems in the credit market;


•	the fair value of any underlying collateral;


•	the existence of any credit protection available;


•	our intent to sell and whether it is more likely than not we would be required to sell prior to recovery for debt securities;


•	our assessment in the case of equity securities including perpetual preferred stocks with credit deterioration that the security cannot recover to cost in a reasonable period of time;


•	our intent and ability to retain equity securities for a period of time sufficient to allow for recovery;


•	consideration of rating agency actions; and


•	changes in estimated cash flows of mortgage and asset backed securities.

We determine whether other than temporary impairment losses should be recognized for debt and equity securities by assessing all facts and circumstances surrounding each security. Where the decline in fair value of debt securities is attributable to changes in market interest rates or to factors such as market volatility, liquidity and spread widening, and we anticipate recovery of all contractual or expected cash flows, we do not consider these investments to be other than temporarily impaired because we do not intend to sell these investments and it is not more likely than not we will be required to sell these investments before a recovery of amortized cost, which may be maturity. For equity securities, we recognize an impairment charge in the period in which we do not have the intent and ability to hold the securities until recovery of cost or we determine that the security will not recover to book value within a reasonable period of time. We determine what constitutes a reasonable period of time on a security-by-security basis by considering all the evidence available to us, including the magnitude of any unrealized loss and its duration.

Other than temporary impairment losses on equity securities are recognized in operations. If we intend to sell a debt security or if it is more likely than not that we will be required to sell a debt security before recovery of its amortized cost basis, other than temporary impairment has occurred and the difference between amortized cost and fair value will be recognized as a loss in operations.

If we do not intend to sell and it is not more likely than not we will be required to sell the debt security but also do not expect to recover the entire amortized cost basis of the security, an impairment loss would be recognized in operations in the amount of the expected credit loss. We determine the amount of expected credit loss by calculating the present value of the cash flows expected to be collected discounted at each security's acquisition yield based on our consideration of whether the security was of high credit quality at the time of acquisition. The difference between the present value of expected future cash flows and the amortized cost basis of the security is the amount of credit loss recognized in operations. The remaining amount of the other than temporary impairment is recognized in other comprehensive income (loss).

The determination of the credit loss component of a mortgage backed security is based on a number of factors. The primary consideration in this evaluation process is the issuer's ability to meet current and future interest and principal payments as contractually stated at time of purchase. Our review of these securities includes an analysis of the cash flow modeling under various default scenarios considering independent third party benchmarks, the seniority of the specific tranche within the structure of the security, the composition of the collateral and the actual default, loss severity and prepayment experience exhibited. With the input of third party assumptions for default projections, loss severity and prepayment expectations, we evaluate the cash flow projections to determine whether the security is performing in accordance with its contractual obligation.

We utilize the models from a leading structured product software specialist serving institutional investors. These models incorporate each security's seniority and cash flow structure. In circumstances where the analysis implies a potential for principal loss at some point in the future, we use the "best estimate" cash flow projection discounted at the security's effective yield at acquisition to determine the amount of our potential credit loss associated with this security. The discounted expected future cash flows equates to our expected recovery value. Any shortfall of the expected recovery when compared to the amortized cost of the security will be recorded as the credit loss component of other than temporary impairment.

The cash flow modeling is performed on a security-by-security basis and incorporates actual cash flows on the residential mortgage backed securities through the current period, as well as the projection of remaining cash flows using a number of assumptions including default rates, prepayment rates and loss severity rates. The default curves we use are tailored to the Prime or Alt-A residential mortgage backed securities that we own, which assume lower default rates and loss severity for Prime securities versus Alt-A securities. These default curves are scaled higher or lower depending on factors such as current underlying mortgage loan performance, rating agency loss projections, loan to value ratios, geographic diversity, as well as other appropriate considerations.

The following table presents the range of significant assumptions used to determine the credit loss component of other than temporary impairments we have recognized on residential mortgage backed securities for the six months ended June 30, 2017 and 2016, which are all senior level tranches within the structure of the securities:



		Discount Rate				Default Rate				Loss Severity
Sector	Vintage	Min		Max		Min		Max		Min		Max
Six months ended June 30, 2017
Prime	2005	7.5	%	7.7	%	8	%	16	%	45	%	50	%
	2007	6.2	%	6.6	%	15	%	19	%	50	%	60	%

Six months ended June 30, 2016
Prime	2005	7.7	%	7.7	%	14	%	14	%	50	%	50	%
	2006	7.3	%	7.3	%	13	%	13	%	50	%	50	%
	2007	6.2	%	6.4	%	18	%	31	%	50	%	55	%
Alt-A	2005	7.4	%	7.4	%	11	%	11	%	60	%	60	%

The determination of the credit loss component of a corporate bond (including redeemable preferred stocks) is based on the underlying financial performance of the issuer and their ability to meet their contractual obligations. Considerations in our evaluation include, but are not limited to, credit rating changes, financial statement and ratio analysis, changes in management, significant changes in credit spreads, breaches of financial covenants and a review of the economic outlook for the industry and markets in which they trade. In circumstances where an issuer appears unlikely to meet its future obligation, or the security's price decline is deemed other than temporary, an estimate of credit loss is determined. Credit loss is calculated using default probabilities as derived from the credit default swaps markets in conjunction with recovery rates derived from independent third party analysis or a best estimate of credit loss. This credit loss rate is then incorporated into a present value calculation based on an expected principal loss in the future discounted at the yield at the date of purchase and compared to amortized cost to determine the amount of credit loss associated with the security.

In addition, for debt securities which we do not intend to sell and it is not more likely than not we will be required to sell, but our intent changes due to changes or events that could not have been reasonably anticipated, an other than temporary impairment charge is recognized. Once an impairment charge has been recorded, we then continue to review the other than temporarily impaired securities for appropriate valuation on an ongoing basis. Unrealized losses may be recognized in future periods through a charge to earnings should we later conclude that the decline in fair value below amortized cost is other than temporary pursuant to our accounting policy described above. The use of different methodologies and assumptions to determine the fair value of investments and the timing and amount of impairments may have a material effect on the amounts presented in our consolidated financial statements.

The following table summarizes other than temporary impairments for the three and six months ended June 30, 2017 and 2016, by asset type:



	Number of Securities	Total OTTI Losses			Portion of OTTI Losses Recognized in (from) Other Comprehensive Income			Net OTTI Losses Recognized in Operations
		(Dollars in thousands)
Three months ended June 30, 2017
Fixed maturity securities, available for sale:
Residential mortgage backed securities	2	$	—		$	(662	)	$	(662	)
Other asset backed securities	1	—			(287		)	(287		)
	3	$	—		$	(949	)	$	(949	)

Three months ended June 30, 2016
Fixed maturity securities, available for sale:
Residential mortgage backed securities	2	$	—		$	(202	)	$	(202	)
Commercial mortgage backed securities	2	(762		)	—			(762		)
Other asset backed securities	1	—			(3,482		)	(3,482		)
	5	$	(762	)	$	(3,684	)	$	(4,446	)

Six months ended June 30, 2017
Fixed maturity securities, available for sale:
Residential mortgage backed securities	5	$	—		$	(803	)	$	(803	)
Other asset backed securities	1	—			(287		)	(287		)
	6	$	—		$	(1,090	)	$	(1,090	)

Six months ended June 30, 2016
Fixed maturity securities, available for sale:
Corporate securities:
Energy	2	$	(642	)	$	—		$	(642	)
Telecommunications	1	(4,462		)	562			(3,900		)
Utilities	1	(136		)	—			(136		)
Residential mortgage backed securities	6	—			(440		)	(440		)
Commercial mortgage backed securities	5	(1,540		)	—			(1,540		)
Other asset backed securities	1	—			(3,482		)	(3,482		)
	16	$	(6,780	)	$	(3,360	)	$	(10,140	)

The cumulative portion of other than temporary impairments determined to be credit losses which have been recognized in operations for debt securities are summarized as follows:



	Three Months Ended June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
	(Dollars in thousands)
Cumulative credit loss at beginning of period	$	(152,577	)	$	(151,518	)	$	(166,375	)	$	(145,824	)
Credit losses on securities for which OTTI has not previously been recognized	—			(762		)	—			(6,218		)
Additional credit losses on securities for which OTTI has previously been recognized	(949		)	(3,684		)	(1,090		)	(3,922		)
Accumulated losses on securities that were disposed of during the period	—			1,556			13,939			1,556
Cumulative credit loss at end of period	$	(153,526	)	$	(154,408	)	$	(153,526	)	$	(154,408	)

The following table summarizes the cumulative noncredit portion of OTTI and the change in fair value since recognition of OTTI, both of which were recognized in other comprehensive income, by major type of security, for securities that are part of our investment portfolio at June 30, 2017 and December 31, 2016:



	Amortized Cost		OTTI Recognized in Other Comprehensive Income			Change in Fair Value Since OTTI was Recognized			Fair Value
	(Dollars in thousands)
June 30, 2017
Fixed maturity securities, available for sale:
Corporate securities	$	10,502	$	(4,263	)	$	9,231		$	15,470
Residential mortgage backed securities	327,388		(169,137		)	204,438			362,689
Other asset backed securities	4,567		(1,356		)	(1,778		)	1,433
	$	342,457	$	(174,756	)	$	211,891		$	379,592
December 31, 2016
Fixed maturity securities, available for sale:
Corporate securities	$	17,549	$	(5,910	)	$	13,566		$	25,205
Residential mortgage backed securities	368,862		(169,941		)	205,854			404,775
Commercial mortgage backed securities	6,596		—			(107		)	6,489
Other asset backed securities	6,683		(1,643		)	(1,566		)	3,474
	$	399,690	$	(177,494	)	$	217,747		$	439,943

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References + Details

Mortgage Loans on Real Estate

6 Months Ended

Jun. 30, 2017

Mortgage Loans on Real Estate [Abstract]

Mortgage Loans on Real Estate

Our mortgage loan portfolio is summarized in the following table. There were commitments outstanding of $46.9 million at June 30, 2017.



	June 30, 2017			December 31, 2016
	(Dollars in thousands)
Principal outstanding	$	2,562,449		$	2,490,619
Loan loss allowance	(7,849		)	(8,427		)
Deferred prepayment fees	(1,209		)	(1,236		)
Carrying value	$	2,553,391		$	2,480,956

The portfolio consists of commercial mortgage loans collateralized by the related properties and diversified as to property type, location and loan size. Our mortgage lending policies establish limits on the amount that can be loaned to one borrower and other criteria to attempt to reduce the risk of default. The mortgage loan portfolio is summarized by geographic region and property type as follows:



	June 30, 2017				December 31, 2016
	Principal		Percent		Principal		Percent
	(Dollars in thousands)
Geographic distribution
East	$	596,587	23.3	%	$	635,434	25.5	%
Middle Atlantic	155,234		6.1	%	151,640		6.1	%
Mountain	302,764		11.8	%	235,932		9.5	%
New England	12,496		0.5	%	12,724		0.5	%
Pacific	423,086		16.5	%	385,683		15.5	%
South Atlantic	542,146		21.2	%	519,065		20.8	%
West North Central	311,126		12.1	%	325,447		13.1	%
West South Central	219,010		8.5	%	224,694		9.0	%
	$	2,562,449	100.0	%	$	2,490,619	100.0	%
Property type distribution
Office	$	291,118	11.4	%	$	308,578	12.4	%
Medical Office	35,248		1.4	%	50,780		2.1	%
Retail	989,810		38.6	%	886,942		35.6	%
Industrial/Warehouse	691,630		27.0	%	700,644		28.1	%
Apartment	377,170		14.7	%	375,837		15.1	%
Mixed use/other	177,473		6.9	%	167,838		6.7	%
	$	2,562,449	100.0	%	$	2,490,619	100.0	%

Our financing receivables currently consist of one portfolio segment which is our commercial mortgage loan portfolio. These are mortgage loans with collateral consisting of commercial real estate and borrowers consisting mostly of limited liability partnerships or limited liability corporations.

We evaluate our mortgage loan portfolio for the establishment of a loan loss allowance by specific identification of impaired loans and the measurement of an estimated loss for each individual loan identified. A mortgage loan is impaired when it is probable that we will be unable to collect all amounts due according to the contractual terms of the loan agreement. If we determine that the value of any specific mortgage loan is impaired, the carrying amount of the mortgage loan will be reduced to its fair value, based upon the present value of expected future cash flows from the loan discounted at the loan's effective interest rate, or the fair value of the underlying collateral less estimated costs to sell.

In addition, we analyze the mortgage loan portfolio for the need of a general loan allowance for probable losses on all other loans on a quantitative and qualitative basis. The amount of the general loan allowance is based upon management's evaluation of the collectability of the loan portfolio, historical loss experience, delinquencies, credit concentrations, underwriting standards and national and local economic conditions.

We rate each of the mortgage loans in our portfolio based on factors such as historical operating performance, loan to value ratio and economic outlook, among others. We calculate a loss factor to apply to each rating based on historical losses we have recognized in our mortgage loan portfolio. We apply the loss factors to the total principal outstanding within each rating category to determine an appropriate estimate of the general loan loss allowance. We also assess the portfolio qualitatively and apply a loss rate to all loans without a specific allowance based on management's assessment of economic conditions, and we apply an additional amount of loss allowance to a group of loans that we have identified as having higher risk of loss.

The following table presents a rollforward of our specific and general valuation allowances for mortgage loans on real estate:



	Three Months Ended June 30, 2017						Three Months Ended June 30, 2016
	Specific Allowance			General Allowance			Specific Allowance			General Allowance
	(Dollars in thousands)
Beginning allowance balance	$	(1,327	)	$	(6,800	)	$	(5,750	)	$	(6,000	)
Charge-offs	—			—			2,101			—
Recoveries	—			—			1,682			—
Change in provision for credit losses	(722		)	1,000			(2,585		)	(300		)
Ending allowance balance	$	(2,049	)	$	(5,800	)	$	(4,552	)	$	(6,300	)

	Six Months Ended June 30, 2017						Six Months Ended June 30, 2016
	Specific Allowance			General Allowance			Specific Allowance			General Allowance
	(Dollars in thousands)
Beginning allowance balance	$	(1,327	)	$	(7,100	)	$	(7,842	)	$	(6,300	)
Charge-offs	—			—			2,101			—
Recoveries	—			—			5,022			—
Change in provision for credit losses	(722		)	1,300			(3,833		)	—
Ending allowance balance	$	(2,049	)	$	(5,800	)	$	(4,552	)	$	(6,300	)

The specific allowance represents the total credit loss allowances on loans which are individually evaluated for impairment. The general allowance is for the group of loans discussed above which are collectively evaluated for impairment. The following table presents the total outstanding principal of loans evaluated for impairment by basis of impairment method:



	June 30, 2017		December 31, 2016
	(Dollars in thousands)
Individually evaluated for impairment	$	6,773	$	4,640
Collectively evaluated for impairment	2,555,676		2,485,979
Total loans evaluated for impairment	$	2,562,449	$	2,490,619

Charge-offs include allowances that have been established on loans that were satisfied either by taking ownership of the collateral or by some other means such as discounted pay-off or loan sale. When ownership of the property is taken it is recorded at the lower of the mortgage loan's carrying value or the property's fair value (based on appraised values) less estimated costs to sell. The real estate owned is recorded as a component of other investments and the mortgage loan is recorded as fully paid, with any allowance for credit loss that has been established charged off. Fair value of the real estate is determined by third party appraisal. Recoveries are situations where we have received a payment from the borrower in an amount greater than the carrying value of the loan (principal outstanding less specific allowance).

We did not own any real estate during the three and six months ended June 30, 2017. The following table summarizes the activity in real estate owned, included in Other investments, which was obtained in satisfaction of mortgage loans on real estate during the three and six months ended June 30, 2016:



	Three Months Ended June 30,			Six Months Ended June 30,
	2016			2016
	(Dollars in thousands)
Real estate owned at beginning of period	$	5,356		$	6,485
Real estate acquired in satisfaction of mortgage loans	—			—
Additions	—			—
Sales	(5,338		)	(6,444		)
Impairments	—			—
Depreciation	(18		)	(41		)
Real estate owned at end of period	$	—		$	—

We analyze credit risk of our mortgage loans by analyzing all available evidence on loans that are delinquent and loans that are in a workout period.



	June 30, 2017		December 31, 2016
	(Dollars in thousands)
Credit Exposure--By Payment Activity
Performing	$	2,558,711	$	2,489,028
In workout	1,516		1,591
Delinquent	—		—
Collateral dependent	2,222		—
	$	2,562,449	$	2,490,619

The loans that are categorized as "in workout" consist of loans that we have agreed to lower or no mortgage payments for a period of time while the borrowers address cash flow and/or operational issues. The key features of these workouts have been determined on a loan-by-loan basis. Most of these loans are in a period of low cash flow due to tenants vacating their space or tenants requesting rent relief during difficult economic periods. Generally, we have allowed the borrower a six month interest only period and in some cases a twelve month period of interest only. Interest only workout loans are expected to return to their regular debt service payments after the interest only period. Interest only loans that are not fully amortizing will have a larger balance at their balloon date than originally contracted. Fully amortizing loans that are in interest only periods will have larger debt service payments for their remaining term due to lost principal payments during the interest only period. In limited circumstances we have allowed borrowers to pay the principal portion of their loan payment into an escrow account that can be used for capital and tenant improvements for a period of not more than twelve months. In these situations new loan amortization schedules are calculated based on the principal not collected during this twelve month workout period and larger payments are collected for the remaining term of each loan. In all cases, the original interest rate and maturity date have not been modified, and we have not forgiven any principal amounts.

Mortgage loans are considered delinquent when they become 60 days or more past due. In general, when loans become 90 days past due, become collateral dependent or enter a period with no debt service payments required we place them on non-accrual status and discontinue recognizing interest income. If payments are received on a delinquent loan, interest income is recognized to the extent it would have been recognized if normal principal and interest would have been received timely. If payments are received to bring a delinquent loan back to current we will resume accruing interest income on that loan. Outstanding principal of loans in non-accrual status at June 30, 2017 totaled $2.2 million. There were no loans in non-accrual status at December 31, 2016.

We define collateral dependent loans as those mortgage loans for which we will depend on the value of the collateral real estate to satisfy the outstanding principal of the loan.

All of our commercial mortgage loans depend on the cash flow of the borrower to be at a sufficient level to service the principal and interest payments as they come due. In general, cash inflows of the borrowers are generated by collecting monthly rent from tenants occupying space within the borrowers' properties. Our borrowers face collateral risks such as tenants going out of business, tenants struggling to make rent payments as they become due, and tenants canceling leases and moving to other locations. We have a number of loans where the real estate is occupied by a single tenant. Our borrowers sometimes face both a reduction in cash flow on their mortgage property as well as a reduction in the fair value of the real estate collateral. If borrowers are unable to replace lost rent revenue and increases in the fair value of their property do not materialize, we could potentially incur more losses than what we have allowed for in our specific and general loan loss allowances.

Aging of financing receivables is summarized in the following table, with loans in a "workout" period as of the reporting date considered current if payments are current in accordance with agreed upon terms:



	30 - 59 Days		60 - 89 Days		90 Days and Over		Total Past Due		Current		Collateral Dependent Receivables		Total Financing Receivables
	(Dollars in thousands)
Commercial Mortgage Loans
June 30, 2017	$	—	$	—	$	—	$	—	$	2,560,227	$	2,222	$	2,562,449
December 31, 2016	$	2,737	$	—	$	—	$	2,737	$	2,487,882	$	—	$	2,490,619

Financing receivables summarized in the following two tables represent all loans that we are either not currently collecting, or those we feel it is probable we will not collect all amounts due according to the contractual terms of the loan agreements (all loans that we have worked with the borrower to alleviate short-term cash flow issues, loans delinquent for 60 days or more at the reporting date, loans we have determined to be collateral dependent and loans that we have recorded specific impairments on that we feel may continue to have performance issues).



	Recorded Investment		Unpaid Principal Balance		Related Allowance
	(Dollars in thousands)
June 30, 2017
Mortgage loans with an allowance	$	4,724	$	6,773	$	(2,049	)
Mortgage loans with no related allowance	1,516		1,516		—
	$	6,240	$	8,289	$	(2,049	)
December 31, 2016
Mortgage loans with an allowance	$	3,313	$	4,640	$	(1,327	)
Mortgage loans with no related allowance	1,591		1,591		—
	$	4,904	$	6,231	$	(1,327	)



	Average Recorded Investment		Interest Income Recognized
	(Dollars in thousands)
Three months ended June 30, 2017
Mortgage loans with an allowance	$	5,107	$	104
Mortgage loans with no related allowance	1,535		23
	$	6,642	$	127
Three months ended June 30, 2016
Mortgage loans with an allowance	$	6,921	$	164
Mortgage loans with no related allowance	4,737		74
	$	11,658	$	238
Six months ended June 30, 2017
Mortgage loans with an allowance	$	5,135	$	207
Mortgage loans with no related allowance	1,553		46
	$	6,688	$	253
Six months ended June 30, 2016
Mortgage loans with an allowance	$	7,166	$	329
Mortgage loans with no related allowance	4,793		150
	$	11,959	$	479

A Troubled Debt Restructuring ("TDR") is a situation where we have granted a concession to a borrower for economic or legal reasons related to the borrower's financial difficulties that we would not otherwise consider. A mortgage loan that has been granted new terms, including workout terms as described previously, would be considered a TDR if it meets conditions that would indicate a borrower is experiencing financial difficulty and the new terms constitute a concession on our part. We analyze all loans where we have agreed to workout terms and all loans that we have refinanced to determine if they meet the definition of a TDR. We consider the following factors in determining whether or not a borrower is experiencing financial difficulty:


•	borrower is in default,


•	borrower has declared bankruptcy,


•	there is growing concern about the borrower's ability to continue as a going concern,


•	borrower has insufficient cash flows to service debt,


•	borrower's inability to obtain funds from other sources, and


•	there is a breach of financial covenants by the borrower.

If the borrower is determined to be in financial difficulty, we consider the following conditions to determine if the borrower was granted a concession:


•	assets used to satisfy debt are less than our recorded investment,


•	interest rate is modified,


•	maturity date extension at an interest rate less than market rate,


•	capitalization of interest,


•	delaying principal and/or interest for a period of three months or more, and


•	partial forgiveness of the balance or charge-off.

Mortgage loan workouts, refinances or restructures that are classified as TDRs are individually evaluated and measured for impairment. A summary of mortgage loans on commercial real estate with outstanding principal at June 30, 2017 and December 31, 2016 that we determined to be TDRs are as follows:



Geographic Region	Number of TDRs	Principal Balance Outstanding		Specific Loan Loss Allowance			Net Carrying Amount
		(Dollars in thousands)
June 30, 2017
South Atlantic	1	$	2,978	$	—		$	2,978
East North Central	1	1,977		(467		)	1,510
	2	$	4,955	$	(467	)	$	4,488
December 31, 2016
South Atlantic	1	$	3,004	$	—		$	3,004
East North Central	1	2,020		(467		)	1,553
	2	$	5,024	$	(467	)	$	4,557

- Definition

The entire disclosure for claims held for amounts due a entity, excluding financing receivables. Examples include, but are not limited to, trade accounts receivables, notes receivables, loans receivables. Includes disclosure for allowance for credit losses.

+ References + Details

Derivative Instruments

6 Months Ended

Jun. 30, 2017

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivative Instruments

None of our derivatives qualify for hedge accounting, thus, any change in the fair value of the derivatives is recognized immediately in the consolidated statements of operations. The fair value of our derivative instruments, including derivative instruments embedded in fixed index annuity contracts, presented in the consolidated balance sheets are as follows:



	June 30, 2017		December 31, 2016
	(Dollars in thousands)
Assets
Derivative instruments
Call options	$	1,086,624	$	830,519
Other assets
Interest rate caps	468		1,082
	$	1,087,092	$	831,601
Liabilities
Policy benefit reserves - annuity products
Fixed index annuities - embedded derivatives	$	7,552,365	$	6,563,288
Other liabilities
Interest rate swap	2,001		2,113
	$	7,554,366	$	6,565,401

The changes in fair value of derivatives included in the unaudited consolidated statements of operations are as follows:



	Three Months Ended June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
	(Dollars in thousands)
Change in fair value of derivatives:
Call options	$	267,705		$	40,394		$	654,441		$	(30,357	)
Interest rate swap	(549		)	(982		)	(474		)	(3,626		)
Interest rate caps	(336		)	(313		)	(614		)	(983		)
	$	266,820		$	39,099		$	653,353		$	(34,966	)
Change in fair value of embedded derivatives:
Fixed index annuities—embedded derivatives	$	3,676		$	199,917		$	79,886		$	379,632
Other changes in difference between policy benefit reserves computed using derivative accounting vs. long-duration contracts accounting	171,297			84,386			319,257			170,528
	$	174,973		$	284,303		$	399,143		$	550,160

The amounts presented as "Other changes in difference between policy benefit reserves computed using derivative accounting vs. long-duration contracts accounting" represents the total change in the difference between policy benefit reserves for fixed index annuities computed under the derivative accounting standard and the long-duration contracts accounting standard at each balance sheet date, less the change in fair value of our fixed index annuities embedded derivatives that is presented as Level 3 liabilities in Note 2.

We have fixed index annuity products that guarantee the return of principal to the policyholder and credit interest based on a percentage of the gain in a specified market index. When fixed index annuity deposits are received, a portion of the deposit is used to purchase derivatives consisting of call options on the applicable market indices to fund the index credits due to fixed index annuity policyholders. Substantially all such call options are one year options purchased to match the funding requirements of the underlying policies. The call options are marked to fair value with the change in fair value included as a component of revenues. The change in fair value of derivatives includes the gains or losses recognized at the expiration of the option term or upon early termination and the changes in fair value for open positions. On the respective anniversary dates of the index policies, the index used to compute the annual index credit is reset and we purchase new one-year call options to fund the next annual index credit. We manage the cost of these purchases through the terms of our fixed index annuities, which permit us to change caps, participation rates, and/or asset fees, subject to guaranteed minimums on each policy's anniversary date. By adjusting caps, participation rates, or asset fees, we can generally manage option costs except in cases where the contractual features would prevent further modifications.

Our strategy attempts to mitigate any potential risk of loss due to the nonperformance of the counterparties to these call options through a regular monitoring process which evaluates the program's effectiveness. We do not purchase call options that would require payment or collateral to another institution and our call options do not contain counterparty credit-risk-related contingent features. We are exposed to risk of loss in the event of nonperformance by the counterparties and, accordingly, we purchase our option contracts from multiple counterparties and evaluate the creditworthiness of all counterparties prior to purchase of the contracts. All of these options have been purchased from nationally recognized financial institutions with a Standard and Poor's credit rating of A- or higher at the time of purchase and the maximum credit exposure to any single counterparty is subject to concentration limits. We also have credit support agreements that allow us to request the counterparty to provide collateral to us when the fair value of our exposure to the counterparty exceeds specified amounts.

The notional amount and fair value of our call options by counterparty and each counterparty's current credit rating are as follows:



			June 30, 2017				December 31, 2016
Counterparty	Credit Rating (S&P)	Credit Rating (Moody's)	Notional Amount		Fair Value		Notional Amount		Fair Value
			(Dollars in thousands)
Bank of America	A+	A1	$	5,020,592	$	179,048	$	5,958,884	$	178,477
Barclays	A-	A1	3,760,675		103,317		3,441,832		89,721
BNP Paribas	A	A1	1,837,242		48,330		1,199,265		19,598
Citibank, N.A.	A+	A1	3,791,993		155,815		4,038,528		97,094
Credit Suisse	A	A1	3,721,586		92,577		2,130,710		44,242
Deutsche Bank	A-	Baa2	—		—		25,935		892
J.P. Morgan	A+	Aa3	1,622,559		53,359		1,785,583		19,645
Morgan Stanley	A+	A1	2,795,503		104,024		2,543,421		64,425
Royal Bank of Canada	AA-	A1	3,167,888		104,644		3,384,310		103,510
SunTrust	A-	Baa1	3,147,079		101,690		2,375,418		72,990
Wells Fargo	AA-	Aa2	3,986,928		131,676		3,850,842		130,545
Exchange traded			407,302		12,144		313,354		9,380
			$	33,259,347	$	1,086,624	$	31,048,082	$	830,519

As of June 30, 2017 and December 31, 2016, we held $1.1 billion and $0.8 billion, respectively, of cash and cash equivalents and other securities from counterparties for derivative collateral, which is included in other liabilities on our consolidated balance sheets. This derivative collateral limits the maximum amount of economic loss due to credit risk that we would incur if parties to the call options failed completely to perform according to the terms of the contracts to $16.9 million and $55.5 million at June 30, 2017 and December 31, 2016, respectively.

The future annual index credits on our fixed index annuities are treated as a "series of embedded derivatives" over the expected life of the applicable contract. We do not purchase call options to fund the index liabilities which may arise after the next policy anniversary date. We must value both the call options and the related forward embedded options in the policies at fair value.

We entered into an interest rate swap and interest rate caps to manage interest rate risk associated with the floating rate component on certain of our subordinated debentures. See Note 10 in our Annual Report on Form 10-K for the year ended December 31, 2016 for more information on our subordinated debentures. The terms of the interest rate swap provide that we pay a fixed rate of interest and receive a floating rate of interest. The terms of the interest rate caps limit the three month London Interbank Offered Rate ("LIBOR") to 2.50%. The interest rate swap and caps are not effective hedges under accounting guidance for derivative instruments and hedging activities. Therefore, we record the interest rate swap and caps at fair value and any net cash payments received or paid are included in the change in fair value of derivatives in the unaudited consolidated statements of operations.

Details regarding the interest rate swap are as follows:



	Notional			Pay			June 30, 2017			December 31, 2016
Maturity Date	Amount		Receive Rate	Rate		Counterparty	Fair Value			Fair Value
							(Dollars in thousands)
March 15, 2021	$	85,500	LIBOR	2.415	%	SunTrust	$	(2,001	)	$	(2,113	)

Details regarding the interest rate caps are as follows:



	Notional			Cap			June 30, 2017		December 31, 2016
Maturity Date	Amount		Floating Rate	Rate		Counterparty	Fair Value		Fair Value
							(Dollars in thousands)
July 7, 2021	$	40,000	LIBOR	2.50	%	SunTrust	$	233	$	542
July 8, 2021	12,000		LIBOR	2.50	%	SunTrust	70		163
July 29, 2021	27,000		LIBOR	2.50	%	SunTrust	165		377
	$	79,000					$	468	$	1,082

The interest rate swap converts floating rates to fixed rates for seven years which began in March 2014. The interest rate caps cap our interest rates for seven years which began in July 2014. As of June 30, 2017, we deposited $1.8 million of collateral with the counterparty to the swap.

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

+ References

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+ Details

Notes and Loan Payable and Amounts Due Under Repurchase Agreements

6 Months Ended

Jun. 30, 2017

Debt Disclosure [Abstract]

Notes and Loan Payable and Amounts Due Under Repurchase Agreements

Notes and loan payable includes the following:



	June 30, 2017			December 31, 2016
	(Dollars in thousands)
Senior notes due 2021
Principal	$	400,000		$	400,000
Unamortized debt issue costs	(5,187		)	(5,733		)
Senior notes due 2027
Principal	500,000			—
Unamortized debt issue costs	(5,804		)	—
Unamortized discount	(349		)	—
Term loan due 2019
Principal	—			100,000
Unamortized debt issue costs	—			(512		)
	$	888,660		$	493,755

On June 16, 2017, we issued $500 million aggregate principal amount of senior unsecured notes due 2027 which bear interest at 5.0% per year and will mature on June 15, 2027 (the "2027 Notes"). The 2027 Notes were issued at a $0.3 million discount, which is being amortized over the term of the 2027 Notes using the effective interest method. Contractual interest is payable semi-annually in arrears each June 15th and December 15th. The initial transaction fees and costs totaling $5.8 million were capitalized as deferred financing costs and are being amortized over the term of the 2027 Notes using the effective interest method. We used the net proceeds from the issuance of the 2027 Notes to prepay our $100 million term loan that was scheduled to mature in 2019 on June 16, 2017, and to redeem our $400 million notes due 2021 (the “2021 Notes”) on July 17, 2017. See Note 9 for further details surrounding the early redemption of the 2021 Notes.

As part of our investment strategy, we enter into securities repurchase agreements (short-term collateralized borrowings). When we do borrow cash on these repurchase agreements, we pledge collateral in the form of debt securities with fair values approximately equal to the amount due and we use the cash to purchase debt securities ahead of the time we collect the cash from selling annuity policies to avoid a lag between the investment of funds and the obligation to credit interest to policyholders. We earn investment income on the securities purchased with these borrowings at a rate in excess of the cost of these borrowings. Such borrowings averaged $36.1 million and $69.1 million during the three and six months ended June 30, 2017, respectively, and the maximum amount borrowed was $274.5 million during the six months ended June 30, 2017. We had no borrowings under repurchase agreements during the three and six months ended June 30, 2016. The weighted average interest rate on amounts due under repurchase agreements was 1.02% and 0.74% for the three and six months ended June 30, 2017.

Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies We are occasionally involved in litigation, both as a defendant and as a plaintiff. In addition, state regulatory bodies, such as state insurance departments, the Securities and Exchange Commission, Financial Industry Regulatory Authority, the Department of Labor, and other regulatory bodies regularly make inquiries and conduct examinations or investigations concerning our compliance with, among other things, insurance laws, securities laws, the Employee Retirement Income Security Act of 1974, as amended, and laws governing the activities of broker/dealers. In accordance with applicable accounting guidelines, we establish an accrued liability for litigation and regulatory matters when those matters present loss contingencies that are both probable and estimable. As a litigation or regulatory matter is developing we, in conjunction with outside counsel, evaluate on an ongoing basis whether the matter presents a loss contingency that meets conditions indicating the need for accrual and/or disclosure, and if not the matter will continue to be monitored for further developments. If and when the loss contingency related to litigation or regulatory matters is deemed to be both probable and estimable, we will establish an accrued liability with respect to that matter and will continue to monitor the matter for further developments that may affect the amount of the accrued liability. There can be no assurance that any pending or future litigation will not have a material adverse effect on our business, financial condition, or results of operations. In addition to our commitments to fund mortgage loans, we have unfunded commitments at June 30, 2017 to limited partnerships of $58.2 million and to secured bank loans of $9.3 million.

Earnings (Loss) Per Share and Stockholders' Equity

6 Months Ended

Jun. 30, 2017

Earnings Per Share [Abstract]

Earnings (Loss) Per Share and Stockholders' Equity

Earnings (Loss) Per Share

The following table sets forth the computation of earnings (loss) per common share and earnings (loss) per common share - assuming dilution:



	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
	(Dollars in thousands, except per share data)
Numerator:
Net income (loss) - numerator for earnings (loss) per common share	$	26,946	$	14,708	$	80,885	$	(30,133	)

Denominator:
Weighted average common shares outstanding (1)	88,897,203		82,516,927		88,772,831		82,322,919
Effect of dilutive securities:
2015 warrants	—		—		—		30,439
Stock options and deferred compensation agreements	850,870		353,052		899,594		422,809
Restricted stock and restricted stock units	364,211		314,158		372,214		296,649
Denominator for earnings (loss) per common share - assuming dilution	90,112,284		83,184,137		90,044,639		83,072,816

Earnings (loss) per common share	$	0.30	$	0.18	$	0.91	$	(0.37	)
Earnings (loss) per common share - assuming dilution	$	0.30	$	0.18	$	0.90	$	(0.37	)


(1)	Weighted average common shares outstanding include shares vested under the NMO Deferred Compensation Plan.

Options to purchase shares of our common stock that were outstanding during the respective periods indicated but were not included in the computation of diluted earnings (loss) per share because the options' exercise price was greater than the average market price of the common shares are as follows:



Period	Number of Shares	Range of Exercise Prices
		Minimum	Maximum
Three months ended June 30, 2017	1,002,391	$24.79	$24.79
Three months ended June 30, 2016	1,061,541	$24.79	$24.79
Six months ended June 30, 2017	1,002,391	$24.79	$24.79
Six months ended June 30, 2016	1,061,541	$24.79	$24.79

Stockholders' Equity

In August 2015, we completed an underwritten public offering of 8,600,000 shares of our common stock at a public offering price of $25.25 per share, of which 4,300,000 shares were subject to a forward sale agreement. The underwriters exercised in full their option to purchase 1,290,000 additional shares of common stock, which were subject to a separate forward sale agreement. We settled the forward sale agreements on August 1, 2016 and issued 5,590,000 shares of our common stock and received $134.7 million in net proceeds. We contributed the net proceeds from the settlement to the capital and surplus of American Equity Life.

The forward sale agreements had no initial fair value since they were entered into at the then market price of the common stock. The forward sale agreements were equity instruments and qualified for an exception from derivative and fair value accounting.

Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2017

Accounting Policies [Abstract]

New Accounting Pronouncements, Policy

Adopted Accounting Pronouncements

In March 2016, the Financial Accounting Standards Board ("FASB") issued an accounting standards update ("ASU") related to the accounting for share-based payment transactions. The aspects of accounting guidance affected by this ASU are income taxes, classification of awards as either equity or liabilities, and classification on the statement of cash flows. We adopted this ASU on January 1, 2017. The adoption of this ASU resulted in an income tax benefit of $0.3 million and $1.6 million being recognized in operations during the three and six month periods ended June 30, 2017 due to the requirement under this standard to recognize excess tax benefits related to share-based payment awards in income tax expense.

New Accounting Pronouncements

In January 2016, the FASB issued an ASU that, among other aspects of recognition, measurement, presentation and disclosure of financial instruments, primarily requires equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income. However, an entity may choose to measure equity investments that do not have readily determinable fair values at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. Additionally, it changes the accounting for financial liabilities measured at fair value under the fair value option and eliminates some disclosures regarding fair value of financial assets and liabilities measured at amortized cost. This ASU will be effective for us on January 1, 2018, and we have not determined the effect it will have on our consolidated financial statements.

In February 2016, the FASB issued an ASU that will require recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. This ASU affects accounting and disclosure more dramatically for lessees as accounting for lessors is mainly unchanged. This ASU will be effective for us on January 1, 2019, with early adoption permitted, and we have not determined the effect it will have on our consolidated financial statements.

In June 2016, the FASB issued an ASU that significantly changes the impairment model for most financial assets that are measured at amortized cost and certain other instruments from an incurred loss model to an expected loss model that requires these assets be presented at the net amount expected to be collected. In addition, credit losses on available for sale debt securities should be recorded through an allowance account. This ASU will be effective for us on January 1, 2020, with early adoption permitted, and we have not yet determined the impact this updated guidance will have on our consolidated financial statements.

In August 2016, the FASB issued an ASU that clarifies how certain cash receipts and cash payments are to be presented and classified in the statement of cash flows. This ASU will be effective for us on January 1, 2018, with early adoption permitted, and we have not yet determined the impact this updated guidance will have on our consolidated financial statements.

In March 2017, the FASB issued an ASU that applies to certain callable debt securities where the amortized cost basis is at a premium to the price repayable by the issuer at the earliest call date. Under this guidance, the premium will be amortized to the first call date. This ASU will be effective for us on January 1, 2019, with early adoption permitted, and we have not yet determined the impact this updated guidance will have on our consolidated financial statements.

Fair Values of Financial Instruments, Policy


Level 1—	Quoted prices are available in active markets for identical financial instruments as of the reporting date. We do not adjust the quoted price for these financial instruments, even in situations where we hold a large position and a sale could reasonably impact the quoted price.


Level 2—	Quoted prices in active markets for similar financial instruments, quoted prices for identical or similar financial instruments in markets that are not active; and models and other valuation methodologies using inputs other than quoted prices that are observable.

Level 3—

Transfers of securities among the levels occur at times and depend on the type of inputs used to determine fair value of each security.

Investments, Policy


•	the length of time and the extent to which the fair value has been less than amortized cost or cost;


•	whether the issuer is current on all payments and all contractual payments have been made as agreed;


•	the remaining payment terms and the financial condition and near-term prospects of the issuer;


•	the lack of ability to refinance due to liquidity problems in the credit market;


•	the fair value of any underlying collateral;


•	the existence of any credit protection available;


•	our intent to sell and whether it is more likely than not we would be required to sell prior to recovery for debt securities;


•	our assessment in the case of equity securities including perpetual preferred stocks with credit deterioration that the security cannot recover to cost in a reasonable period of time;


•	our intent and ability to retain equity securities for a period of time sufficient to allow for recovery;


•	consideration of rating agency actions; and


•	changes in estimated cash flows of mortgage and asset backed securities.

Mortgage Loans on Real Estate, Allowance for Loan Losses, Policy

Mortgage Loans on Real Estate, Real Estate Acquired Through Foreclosure, Policy

Mortgage Loans on Real Estate, Non-Accrual Loan Status, Policy

Mortgage Loans on Real Estate, Troubled Debt Restructuring, Policy


•	borrower is in default,


•	borrower has declared bankruptcy,


•	there is growing concern about the borrower's ability to continue as a going concern,


•	borrower has insufficient cash flows to service debt,


•	borrower's inability to obtain funds from other sources, and


•	there is a breach of financial covenants by the borrower.

If the borrower is determined to be in financial difficulty, we consider the following conditions to determine if the borrower was granted a concession:


•	assets used to satisfy debt are less than our recorded investment,


•	interest rate is modified,


•	maturity date extension at an interest rate less than market rate,


•	capitalization of interest,


•	delaying principal and/or interest for a period of three months or more, and


•	partial forgiveness of the balance or charge-off.

Mortgage loan workouts, refinances or restructures that are classified as TDRs are individually evaluated and measured for impairment.

Commitments and Contingencies, Policy

In accordance with applicable accounting guidelines, we establish an accrued liability for litigation and regulatory matters when those matters present loss contingencies that are both probable and estimable. As a litigation or regulatory matter is developing we, in conjunction with outside counsel, evaluate on an ongoing basis whether the matter presents a loss contingency that meets conditions indicating the need for accrual and/or disclosure, and if not the matter will continue to be monitored for further developments. If and when the loss contingency related to litigation or regulatory matters is deemed to be both probable and estimable, we will establish an accrued liability with respect to that matter and will continue to monitor the matter for further developments that may affect the amount of the accrued liability.

- Definition

Disclosure of accounting policy for investments in financial assets, including marketable securities (debt and equity securities with readily determinable fair values), investments accounted for under the equity method and cost method, securities borrowed and loaned, and repurchase and resale agreements. For marketable securities, the disclosure may include the entity's accounting treatment for transfers between investment categories and how the fair values for such securities are determined. Also, for all investments, an entity may describe its policy for assessing, recognizing and measuring impairment of the investment.

+ References + Details

Fair Values of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Carrying Amounts and Fair Values of Financial Instruments

The following sets forth a comparison of the carrying amounts and fair values of our financial instruments:



	June 30, 2017				December 31, 2016
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
	(Dollars in thousands)
Assets
Fixed maturity securities:
Available for sale	$	43,893,785	$	43,893,785	$	41,060,494	$	41,060,494
Held for investment	76,931		76,702		76,825		68,766
Mortgage loans on real estate	2,553,391		2,554,995		2,480,956		2,522,035
Derivative instruments	1,086,624		1,086,624		830,519		830,519
Other investments	314,421		305,551		308,774		300,918
Cash and cash equivalents	1,574,913		1,574,913		791,266		791,266
Coinsurance deposits	4,710,650		4,213,996		4,639,492		4,150,792
Interest rate caps	468		468		1,082		1,082
Counterparty collateral	144,283		144,283		145,693		145,693

Liabilities
Policy benefit reserves	53,546,680		44,785,605		51,280,331		43,104,183
Single premium immediate annuity (SPIA) benefit reserves	286,856		296,948		297,724		308,028
Notes and loan payable	888,660		929,437		493,755		519,440
Subordinated debentures	242,045		245,190		241,853		225,106
Amounts due under repurchase agreements	61,673		61,673		—		—
Interest rate swap	2,001		2,001		2,113		2,113

Assets and Liabilities Measured at Fair Value on a Recurring Basis, By Fair Value Hierarchy Level

Our assets and liabilities which are measured at fair value on a recurring basis as of June 30, 2017 and December 31, 2016 are presented below based on the fair value hierarchy levels:



	Total Fair Value		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(Dollars in thousands)
June 30, 2017
Assets
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	12,174	$	5,807	$	6,367	$	—
United States Government sponsored agencies	1,340,839		—		1,340,839		—
United States municipalities, states and territories	4,137,714		—		4,137,714		—
Foreign government obligations	238,869		—		238,869		—
Corporate securities	29,287,071		6		29,287,065		—
Residential mortgage backed securities	1,181,850		—		1,181,850		—
Commercial mortgage backed securities	5,540,383		—		5,540,383		—
Other asset backed securities	2,154,885		—		2,154,885		—
Other investments: equity securities, available for sale	7,982		—		7,982		—
Derivative instruments	1,086,624		—		1,086,624		—
Cash and cash equivalents	1,574,913		1,574,913		—		—
Interest rate caps	468		—		468		—
Counterparty collateral	144,283		—		144,283		—
	$	46,708,055	$	1,580,726	$	45,127,329	$	—
Liabilities
Interest rate swap	$	2,001	$	—	$	2,001	$	—
Fixed index annuities - embedded derivatives	7,552,365		—		—		7,552,365
	$	7,554,366	$	—	$	2,001	$	7,552,365

December 31, 2016
Assets
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	11,805	$	5,381	$	6,424	$	—
United States Government sponsored agencies	1,344,787		—		1,344,787		—
United States municipalities, states and territories	3,926,950		—		3,926,950		—
Foreign government obligations	236,341		—		236,341		—
Corporate securities	27,114,418		6		27,114,412		—
Residential mortgage backed securities	1,254,835		—		1,254,835		—
Commercial mortgage backed securities	5,365,235		—		5,365,235		—
Other asset backed securities	1,806,123		—		1,806,123		—
Other investments: equity securities, available for sale	8,000		—		8,000		—
Derivative instruments	830,519		—		830,519		—
Cash and cash equivalents	791,266		791,266		—		—
Interest rate caps	1,082		—		1,082		—
Counterparty collateral	145,693		—		145,693		—
	$	42,837,054	$	796,653	$	42,040,401	$	—
Liabilities
Interest rate swap	$	2,113	$	—	$	2,113	$	—
Fixed index annuities - embedded derivatives	6,563,288		—		—		6,563,288
	$	6,565,401	$	—	$	2,113	$	6,563,288

Schedule of Assumptions Used in Estimating Fair Value

The following table presents average lapse rate and partial withdrawal rate assumptions, by contract duration, used in estimating the fair value of the embedded derivative component of our fixed index annuity policy benefit reserves at each reporting date:



	Average Lapse Rates		Average Partial Withdrawal Rates
Contract Duration (Years)	June 30, 2017	December 31, 2016	June 30, 2017	December 31, 2016
1 - 5	1.95%	1.76%	3.31%	3.30%
6 - 10	6.85%	6.58%	3.32%	3.30%
11 - 15	11.28%	11.25%	3.33%	3.32%
16 - 20	11.99%	12.04%	3.19%	3.18%
20+	11.65%	11.68%	3.19%	3.18%

Liabilities Measured at Fair Value on Recurring Basis, Level 3 Reconciliation



	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
	(Dollars in thousands)
Fixed index annuities - embedded derivatives
Beginning balance	$	7,051,000	$	6,254,466	$	6,563,288	$	5,983,622
Premiums less benefits	497,689		44,632		909,191		135,761
Change in fair value, net	3,676		199,917		79,886		379,632
Ending balance	$	7,552,365	$	6,499,015	$	7,552,365	$	6,499,015

Investments (Tables)

6 Months Ended

Jun. 30, 2017

Investments [Abstract]

Schedule of Fixed Maturity Securities

At June 30, 2017 and December 31, 2016, the amortized cost and fair value of fixed maturity securities were as follows:



	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(Dollars in thousands)
June 30, 2017
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	12,114	$	228	$	(168	)	$	12,174
United States Government sponsored agencies	1,348,391		30,288		(37,840		)	1,340,839
United States municipalities, states and territories	3,777,760		369,526		(9,572		)	4,137,714
Foreign government obligations	228,896		12,462		(2,489		)	238,869
Corporate securities	27,813,420		1,656,805		(183,154		)	29,287,071
Residential mortgage backed securities	1,090,846		93,316		(2,312		)	1,181,850
Commercial mortgage backed securities	5,519,767		89,865		(69,249		)	5,540,383
Other asset backed securities	2,116,550		51,796		(13,461		)	2,154,885
	$	41,907,744	$	2,304,286	$	(318,245	)	$	43,893,785
Held for investment:
Corporate security	$	76,931	$	—	$	(229	)	$	76,702

Other investments: equity securities, available for sale:
Finance, insurance, and real estate	$	7,525	$	457	$	—		$	7,982

December 31, 2016
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	11,864	$	229	$	(288	)	$	11,805
United States Government sponsored agencies	1,368,340		23,360		(46,913		)	1,344,787
United States municipalities, states and territories	3,626,395		322,948		(22,393		)	3,926,950
Foreign government obligations	229,589		11,832		(5,080		)	236,341
Corporate securities	26,333,213		1,149,978		(368,773		)	27,114,418
Residential mortgage backed securities	1,166,944		91,445		(3,554		)	1,254,835
Commercial mortgage backed securities	5,422,255		59,994		(117,014		)	5,365,235
Other asset backed securities	1,795,355		31,471		(20,703		)	1,806,123
	$	39,953,955	$	1,691,257	$	(584,718	)	$	41,060,494
Held for investment:
Corporate security	$	76,825	$	—	$	(8,059	)	$	68,766

Other investments: equity securities, available for sale:
Finance, insurance, and real estate	$	7,521	$	479	$	—		$	8,000

Schedule of Fixed Maturity Securities by Contractual Maturity Date



	Available for sale				Held for investment
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
	(Dollars in thousands)
Due in one year or less	$	287,042	$	294,085	$	—	$	—
Due after one year through five years	3,482,397		3,645,145		—		—
Due after five years through ten years	11,828,053		12,116,887		—		—
Due after ten years through twenty years	8,981,750		9,715,165		—		—
Due after twenty years	8,601,339		9,245,385		76,931		76,702
	33,180,581		35,016,667		76,931		76,702
Residential mortgage backed securities	1,090,846		1,181,850		—		—
Commercial mortgage backed securities	5,519,767		5,540,383		—		—
Other asset backed securities	2,116,550		2,154,885		—		—
	$	41,907,744	$	43,893,785	$	76,931	$	76,702

Schedule of Components of Net Unrealized Gains on Available for Sale Fixed Maturity and Equity Securities Reported as Separate Component of Stockholders' Equity

Net unrealized gains on available for sale fixed maturity securities and equity securities reported as a separate component of stockholders' equity were comprised of the following:



	June 30, 2017			December 31, 2016
	(Dollars in thousands)
Net unrealized gains on available for sale fixed maturity securities and equity securities	$	1,986,498		$	1,107,018
Adjustments for assumed changes in amortization of deferred policy acquisition costs and deferred sales inducements	(1,082,516		)	(618,661		)
Deferred income tax valuation allowance reversal	22,534			22,534
Deferred income tax expense	(316,394		)	(170,925		)
Net unrealized gains reported as accumulated other comprehensive income	$	610,122		$	339,966

Schedule of Credit Quality of Fixed Maturity Security Portfolio by NAIC Designation

The following table summarizes the credit quality, as determined by NAIC designation, of our fixed maturity portfolio as of the dates indicated:



	June 30, 2017				December 31, 2016
NAIC Designation	Amortized Cost		Fair Value		Amortized Cost		Fair Value
	(Dollars in thousands)
1	$	26,718,443	$	28,144,706	$	25,607,268	$	26,507,798
2	13,907,192		14,499,548		13,037,592		13,295,648
3	1,229,695		1,207,581		1,201,059		1,155,702
4	97,349		89,144		154,226		137,188
5	19,559		20,698		17,475		24,664
6	12,437		8,810		13,160		8,260
	$	41,984,675	$	43,970,487	$	40,030,780	$	41,129,260

Schedule of Gross Unrealized Losses on Investments, By Category and Length of Time



	Less than 12 months					12 months or more					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
	(Dollars in thousands)
June 30, 2017
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	6,867	$	(168	)	$	—	$	—		$	6,867	$	(168	)
United States Government sponsored agencies	945,126		(35,343		)	49,503		(2,497		)	994,629		(37,840		)
United States municipalities, states and territories	273,302		(9,572		)	—		—			273,302		(9,572		)
Foreign government obligations	—		—			11,844		(2,489		)	11,844		(2,489		)
Corporate securities:
Finance, insurance and real estate	1,132,134		(37,599		)	86,335		(1,495		)	1,218,469		(39,094		)
Manufacturing, construction and mining	458,458		(9,156		)	200,709		(13,648		)	659,167		(22,804		)
Utilities and related sectors	523,863		(14,319		)	43,553		(2,612		)	567,416		(16,931		)
Wholesale/retail trade	282,589		(9,583		)	42,120		(4,812		)	324,709		(14,395		)
Services, media and other	1,156,695		(33,573		)	619,260		(56,357		)	1,775,955		(89,930		)
Residential mortgage backed securities	40,684		(1,631		)	8,036		(681		)	48,720		(2,312		)
Commercial mortgage backed securities	1,924,949		(44,461		)	439,081		(24,788		)	2,364,030		(69,249		)
Other asset backed securities	528,570		(6,387		)	65,296		(7,074		)	593,866		(13,461		)
	$	7,273,237	$	(201,792	)	$	1,565,737	$	(116,453	)	$	8,838,974	$	(318,245	)
Held for investment:
Corporate security:
Insurance	$	—	$	—		$	76,702	$	(229	)	$	76,702	$	(229	)

December 31, 2016
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	7,405	$	(288	)	$	—	$	—		$	7,405	$	(288	)
United States Government sponsored agencies	995,548		(46,913		)	—		—			995,548		(46,913		)
United States municipalities, states and territories	463,409		(22,393		)	—		—			463,409		(22,393		)
Foreign government obligations	29,158		(913		)	20,388		(4,167		)	49,546		(5,080		)
Corporate securities:
Finance, insurance and real estate	1,940,107		(70,421		)	82,907		(7,723		)	2,023,014		(78,144		)
Manufacturing, construction and mining	1,199,420		(34,304		)	311,591		(23,273		)	1,511,011		(57,577		)
Utilities and related sectors	1,401,650		(45,015		)	58,597		(5,820		)	1,460,247		(50,835		)
Wholesale/retail trade	637,121		(18,880		)	29,719		(1,930		)	666,840		(20,810		)
Services, media and other	2,539,519		(82,196		)	716,857		(79,211		)	3,256,376		(161,407		)
Residential mortgage backed securities	81,762		(3,463		)	1,853		(91		)	83,615		(3,554		)
Commercial mortgage backed securities	3,148,395		(116,938		)	895		(76		)	3,149,290		(117,014		)
Other asset backed securities	751,533		(12,289		)	146,167		(8,414		)	897,700		(20,703		)
	$	13,195,027	$	(454,013	)	$	1,368,974	$	(130,705	)	$	14,564,001	$	(584,718	)
Held for investment:
Corporate security:
Insurance	$	—	$	—		$	68,766	$	(8,059	)	$	68,766	$	(8,059	)

Schedule of Changes in Net Unrealized Gains/Losses on Investments

Changes in net unrealized gains on investments for the three and six months ended June 30, 2017 and 2016 are as follows:



	Three Months Ended June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
	(Dollars in thousands)
Fixed maturity securities held for investment carried at amortized cost	$	9,806		$	820		$	7,830		$	3,065
Investments carried at fair value:
Fixed maturity securities, available for sale	$	598,408		$	1,167,861		$	879,502		$	2,282,946
Equity securities, available for sale	(9		)	(1		)	(22		)	(18		)
	598,399			1,167,860			879,480			2,282,928
Adjustment for effect on other balance sheet accounts:
Deferred policy acquisition costs and deferred sales inducements	(312,893		)	(609,224		)	(463,855		)	(1,218,975		)
Deferred income tax asset/liability	(99,927		)	(195,523		)	(145,469		)	(372,384		)
	(412,820		)	(804,747		)	(609,324		)	(1,591,359		)
Change in net unrealized gains on investments carried at fair value	$	185,579		$	363,113		$	270,156		$	691,569

Net Realized Gains (Losses) on Investments

Net realized gains on investments, excluding net OTTI losses for the three and six months ended June 30, 2017 and 2016, are as follows:



	Three Months Ended June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
	(Dollars in thousands)
Available for sale fixed maturity securities:
Gross realized gains	$	4,479		$	4,604		$	10,051		$	6,091
Gross realized losses	(899		)	(1,368		)	(4,462		)	(2,599		)
	3,580			3,236			5,589			3,492
Other investments:
Gain on sale of real estate	15			705			44			836
Loss on sale of real estate	—			(1		)	—			(93		)
	15			704			44			743
Mortgage loans on real estate:
Decrease (increase) in allowance for credit losses	278			(2,885		)	578			(3,833		)
Recovery of specific allowance	—			1,682			—			5,022
	278			(1,203		)	578			1,189
	$	3,873		$	2,737		$	6,211		$	5,424

Significant Assumptions Used to Determine the Credit Loss Component of Other Than Temporary Impairment on Residential Mortgage Backed Securities



		Discount Rate				Default Rate				Loss Severity
Sector	Vintage	Min		Max		Min		Max		Min		Max
Six months ended June 30, 2017
Prime	2005	7.5	%	7.7	%	8	%	16	%	45	%	50	%
	2007	6.2	%	6.6	%	15	%	19	%	50	%	60	%

Six months ended June 30, 2016
Prime	2005	7.7	%	7.7	%	14	%	14	%	50	%	50	%
	2006	7.3	%	7.3	%	13	%	13	%	50	%	50	%
	2007	6.2	%	6.4	%	18	%	31	%	50	%	55	%
Alt-A	2005	7.4	%	7.4	%	11	%	11	%	60	%	60	%

Other Than Temporary Impairment by Asset Type

The following table summarizes other than temporary impairments for the three and six months ended June 30, 2017 and 2016, by asset type:



	Number of Securities	Total OTTI Losses			Portion of OTTI Losses Recognized in (from) Other Comprehensive Income			Net OTTI Losses Recognized in Operations
		(Dollars in thousands)
Three months ended June 30, 2017
Fixed maturity securities, available for sale:
Residential mortgage backed securities	2	$	—		$	(662	)	$	(662	)
Other asset backed securities	1	—			(287		)	(287		)
	3	$	—		$	(949	)	$	(949	)

Three months ended June 30, 2016
Fixed maturity securities, available for sale:
Residential mortgage backed securities	2	$	—		$	(202	)	$	(202	)
Commercial mortgage backed securities	2	(762		)	—			(762		)
Other asset backed securities	1	—			(3,482		)	(3,482		)
	5	$	(762	)	$	(3,684	)	$	(4,446	)

Six months ended June 30, 2017
Fixed maturity securities, available for sale:
Residential mortgage backed securities	5	$	—		$	(803	)	$	(803	)
Other asset backed securities	1	—			(287		)	(287		)
	6	$	—		$	(1,090	)	$	(1,090	)

Six months ended June 30, 2016
Fixed maturity securities, available for sale:
Corporate securities:
Energy	2	$	(642	)	$	—		$	(642	)
Telecommunications	1	(4,462		)	562			(3,900		)
Utilities	1	(136		)	—			(136		)
Residential mortgage backed securities	6	—			(440		)	(440		)
Commercial mortgage backed securities	5	(1,540		)	—			(1,540		)
Other asset backed securities	1	—			(3,482		)	(3,482		)
	16	$	(6,780	)	$	(3,360	)	$	(10,140	)

Other Than Temporary Impairment, Credit Losses Recognized in Earnings

The cumulative portion of other than temporary impairments determined to be credit losses which have been recognized in operations for debt securities are summarized as follows:



	Three Months Ended June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
	(Dollars in thousands)
Cumulative credit loss at beginning of period	$	(152,577	)	$	(151,518	)	$	(166,375	)	$	(145,824	)
Credit losses on securities for which OTTI has not previously been recognized	—			(762		)	—			(6,218		)
Additional credit losses on securities for which OTTI has previously been recognized	(949		)	(3,684		)	(1,090		)	(3,922		)
Accumulated losses on securities that were disposed of during the period	—			1,556			13,939			1,556
Cumulative credit loss at end of period	$	(153,526	)	$	(154,408	)	$	(153,526	)	$	(154,408	)

Schedule of Other Than Temporary Impairment Losses, Investments



	Amortized Cost		OTTI Recognized in Other Comprehensive Income			Change in Fair Value Since OTTI was Recognized			Fair Value
	(Dollars in thousands)
June 30, 2017
Fixed maturity securities, available for sale:
Corporate securities	$	10,502	$	(4,263	)	$	9,231		$	15,470
Residential mortgage backed securities	327,388		(169,137		)	204,438			362,689
Other asset backed securities	4,567		(1,356		)	(1,778		)	1,433
	$	342,457	$	(174,756	)	$	211,891		$	379,592
December 31, 2016
Fixed maturity securities, available for sale:
Corporate securities	$	17,549	$	(5,910	)	$	13,566		$	25,205
Residential mortgage backed securities	368,862		(169,941		)	205,854			404,775
Commercial mortgage backed securities	6,596		—			(107		)	6,489
Other asset backed securities	6,683		(1,643		)	(1,566		)	3,474
	$	399,690	$	(177,494	)	$	217,747		$	439,943

Mortgage Loans on Real Estate (Tables)

6 Months Ended

Jun. 30, 2017

Mortgage Loans on Real Estate [Abstract]

Summary of Mortgage Loan Portfolio

Our mortgage loan portfolio is summarized in the following table. There were commitments outstanding of $46.9 million at June 30, 2017.



	June 30, 2017			December 31, 2016
	(Dollars in thousands)
Principal outstanding	$	2,562,449		$	2,490,619
Loan loss allowance	(7,849		)	(8,427		)
Deferred prepayment fees	(1,209		)	(1,236		)
Carrying value	$	2,553,391		$	2,480,956

Mortgage Loan Portfolio Summarized by Geographic Region and Property Type

The mortgage loan portfolio is summarized by geographic region and property type as follows:



	June 30, 2017				December 31, 2016
	Principal		Percent		Principal		Percent
	(Dollars in thousands)
Geographic distribution
East	$	596,587	23.3	%	$	635,434	25.5	%
Middle Atlantic	155,234		6.1	%	151,640		6.1	%
Mountain	302,764		11.8	%	235,932		9.5	%
New England	12,496		0.5	%	12,724		0.5	%
Pacific	423,086		16.5	%	385,683		15.5	%
South Atlantic	542,146		21.2	%	519,065		20.8	%
West North Central	311,126		12.1	%	325,447		13.1	%
West South Central	219,010		8.5	%	224,694		9.0	%
	$	2,562,449	100.0	%	$	2,490,619	100.0	%
Property type distribution
Office	$	291,118	11.4	%	$	308,578	12.4	%
Medical Office	35,248		1.4	%	50,780		2.1	%
Retail	989,810		38.6	%	886,942		35.6	%
Industrial/Warehouse	691,630		27.0	%	700,644		28.1	%
Apartment	377,170		14.7	%	375,837		15.1	%
Mixed use/other	177,473		6.9	%	167,838		6.7	%
	$	2,562,449	100.0	%	$	2,490,619	100.0	%

Rollforward of Allowance for Credit Losses

The following table presents a rollforward of our specific and general valuation allowances for mortgage loans on real estate:



	Three Months Ended June 30, 2017						Three Months Ended June 30, 2016
	Specific Allowance			General Allowance			Specific Allowance			General Allowance
	(Dollars in thousands)
Beginning allowance balance	$	(1,327	)	$	(6,800	)	$	(5,750	)	$	(6,000	)
Charge-offs	—			—			2,101			—
Recoveries	—			—			1,682			—
Change in provision for credit losses	(722		)	1,000			(2,585		)	(300		)
Ending allowance balance	$	(2,049	)	$	(5,800	)	$	(4,552	)	$	(6,300	)

	Six Months Ended June 30, 2017						Six Months Ended June 30, 2016
	Specific Allowance			General Allowance			Specific Allowance			General Allowance
	(Dollars in thousands)
Beginning allowance balance	$	(1,327	)	$	(7,100	)	$	(7,842	)	$	(6,300	)
Charge-offs	—			—			2,101			—
Recoveries	—			—			5,022			—
Change in provision for credit losses	(722		)	1,300			(3,833		)	—
Ending allowance balance	$	(2,049	)	$	(5,800	)	$	(4,552	)	$	(6,300	)

Impaired Mortgage Loans on Real Estate by Basis of Impairment

The following table presents the total outstanding principal of loans evaluated for impairment by basis of impairment method:



	June 30, 2017		December 31, 2016
	(Dollars in thousands)
Individually evaluated for impairment	$	6,773	$	4,640
Collectively evaluated for impairment	2,555,676		2,485,979
Total loans evaluated for impairment	$	2,562,449	$	2,490,619

Real Estate Acquired Via Foreclosure or Deed In Lieu

The following table summarizes the activity in real estate owned, included in Other investments, which was obtained in satisfaction of mortgage loans on real estate during the three and six months ended June 30, 2016:



	Three Months Ended June 30,			Six Months Ended June 30,
	2016			2016
	(Dollars in thousands)
Real estate owned at beginning of period	$	5,356		$	6,485
Real estate acquired in satisfaction of mortgage loans	—			—
Additions	—			—
Sales	(5,338		)	(6,444		)
Impairments	—			—
Depreciation	(18		)	(41		)
Real estate owned at end of period	$	—		$	—

Mortgage Loans By Credit Quality Indicator

We analyze credit risk of our mortgage loans by analyzing all available evidence on loans that are delinquent and loans that are in a workout period.



	June 30, 2017		December 31, 2016
	(Dollars in thousands)
Credit Exposure--By Payment Activity
Performing	$	2,558,711	$	2,489,028
In workout	1,516		1,591
Delinquent	—		—
Collateral dependent	2,222		—
	$	2,562,449	$	2,490,619

Aging of Financing Receivables



	30 - 59 Days		60 - 89 Days		90 Days and Over		Total Past Due		Current		Collateral Dependent Receivables		Total Financing Receivables
	(Dollars in thousands)
Commercial Mortgage Loans
June 30, 2017	$	—	$	—	$	—	$	—	$	2,560,227	$	2,222	$	2,562,449
December 31, 2016	$	2,737	$	—	$	—	$	2,737	$	2,487,882	$	—	$	2,490,619

Impaired Financing Receivables



	Recorded Investment		Unpaid Principal Balance		Related Allowance
	(Dollars in thousands)
June 30, 2017
Mortgage loans with an allowance	$	4,724	$	6,773	$	(2,049	)
Mortgage loans with no related allowance	1,516		1,516		—
	$	6,240	$	8,289	$	(2,049	)
December 31, 2016
Mortgage loans with an allowance	$	3,313	$	4,640	$	(1,327	)
Mortgage loans with no related allowance	1,591		1,591		—
	$	4,904	$	6,231	$	(1,327	)



	Average Recorded Investment		Interest Income Recognized
	(Dollars in thousands)
Three months ended June 30, 2017
Mortgage loans with an allowance	$	5,107	$	104
Mortgage loans with no related allowance	1,535		23
	$	6,642	$	127
Three months ended June 30, 2016
Mortgage loans with an allowance	$	6,921	$	164
Mortgage loans with no related allowance	4,737		74
	$	11,658	$	238
Six months ended June 30, 2017
Mortgage loans with an allowance	$	5,135	$	207
Mortgage loans with no related allowance	1,553		46
	$	6,688	$	253
Six months ended June 30, 2016
Mortgage loans with an allowance	$	7,166	$	329
Mortgage loans with no related allowance	4,793		150
	$	11,959	$	479

Troubled Debt Restructurings on Financing Receivables

A summary of mortgage loans on commercial real estate with outstanding principal at June 30, 2017 and December 31, 2016 that we determined to be TDRs are as follows:



Geographic Region	Number of TDRs	Principal Balance Outstanding		Specific Loan Loss Allowance			Net Carrying Amount
		(Dollars in thousands)
June 30, 2017
South Atlantic	1	$	2,978	$	—		$	2,978
East North Central	1	1,977		(467		)	1,510
	2	$	4,955	$	(467	)	$	4,488
December 31, 2016
South Atlantic	1	$	3,004	$	—		$	3,004
East North Central	1	2,020		(467		)	1,553
	2	$	5,024	$	(467	)	$	4,557

Derivative Instruments (Tables)

6 Months Ended

Jun. 30, 2017

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Fair Value of Derivative Instruments as Presented in the Consolidated Balance Sheets

The fair value of our derivative instruments, including derivative instruments embedded in fixed index annuity contracts, presented in the consolidated balance sheets are as follows:



	June 30, 2017		December 31, 2016
	(Dollars in thousands)
Assets
Derivative instruments
Call options	$	1,086,624	$	830,519
Other assets
Interest rate caps	468		1,082
	$	1,087,092	$	831,601
Liabilities
Policy benefit reserves - annuity products
Fixed index annuities - embedded derivatives	$	7,552,365	$	6,563,288
Other liabilities
Interest rate swap	2,001		2,113
	$	7,554,366	$	6,565,401

Schedule of Changes in Fair Value of Derivative Instruments

The changes in fair value of derivatives included in the unaudited consolidated statements of operations are as follows:



	Three Months Ended June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
	(Dollars in thousands)
Change in fair value of derivatives:
Call options	$	267,705		$	40,394		$	654,441		$	(30,357	)
Interest rate swap	(549		)	(982		)	(474		)	(3,626		)
Interest rate caps	(336		)	(313		)	(614		)	(983		)
	$	266,820		$	39,099		$	653,353		$	(34,966	)
Change in fair value of embedded derivatives:
Fixed index annuities—embedded derivatives	$	3,676		$	199,917		$	79,886		$	379,632
Other changes in difference between policy benefit reserves computed using derivative accounting vs. long-duration contracts accounting	171,297			84,386			319,257			170,528
	$	174,973		$	284,303		$	399,143		$	550,160

Schedule of Call Options by Counterparty

The notional amount and fair value of our call options by counterparty and each counterparty's current credit rating are as follows:



			June 30, 2017				December 31, 2016
Counterparty	Credit Rating (S&P)	Credit Rating (Moody's)	Notional Amount		Fair Value		Notional Amount		Fair Value
			(Dollars in thousands)
Bank of America	A+	A1	$	5,020,592	$	179,048	$	5,958,884	$	178,477
Barclays	A-	A1	3,760,675		103,317		3,441,832		89,721
BNP Paribas	A	A1	1,837,242		48,330		1,199,265		19,598
Citibank, N.A.	A+	A1	3,791,993		155,815		4,038,528		97,094
Credit Suisse	A	A1	3,721,586		92,577		2,130,710		44,242
Deutsche Bank	A-	Baa2	—		—		25,935		892
J.P. Morgan	A+	Aa3	1,622,559		53,359		1,785,583		19,645
Morgan Stanley	A+	A1	2,795,503		104,024		2,543,421		64,425
Royal Bank of Canada	AA-	A1	3,167,888		104,644		3,384,310		103,510
SunTrust	A-	Baa1	3,147,079		101,690		2,375,418		72,990
Wells Fargo	AA-	Aa2	3,986,928		131,676		3,850,842		130,545
Exchange traded			407,302		12,144		313,354		9,380
			$	33,259,347	$	1,086,624	$	31,048,082	$	830,519

Schedule of Interest Rate Derivatives

Details regarding the interest rate swap are as follows:



	Notional			Pay			June 30, 2017			December 31, 2016
Maturity Date	Amount		Receive Rate	Rate		Counterparty	Fair Value			Fair Value
							(Dollars in thousands)
March 15, 2021	$	85,500	LIBOR	2.415	%	SunTrust	$	(2,001	)	$	(2,113	)

Details regarding the interest rate caps are as follows:



	Notional			Cap			June 30, 2017		December 31, 2016
Maturity Date	Amount		Floating Rate	Rate		Counterparty	Fair Value		Fair Value
							(Dollars in thousands)
July 7, 2021	$	40,000	LIBOR	2.50	%	SunTrust	$	233	$	542
July 8, 2021	12,000		LIBOR	2.50	%	SunTrust	70		163
July 29, 2021	27,000		LIBOR	2.50	%	SunTrust	165		377
	$	79,000					$	468	$	1,082

- Definition

Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.

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+ Details

Notes and Loan Payable and Amounts Due Under Repurchase Agreements (Tables)

6 Months Ended

Jun. 30, 2017

Debt Disclosure [Abstract]

Schedule of Notes and Loan Payable

Notes and loan payable includes the following:



	June 30, 2017			December 31, 2016
	(Dollars in thousands)
Senior notes due 2021
Principal	$	400,000		$	400,000
Unamortized debt issue costs	(5,187		)	(5,733		)
Senior notes due 2027
Principal	500,000			—
Unamortized debt issue costs	(5,804		)	—
Unamortized discount	(349		)	—
Term loan due 2019
Principal	—			100,000
Unamortized debt issue costs	—			(512		)
	$	888,660		$	493,755

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Earnings (Loss) Per Share and Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2017

Earnings Per Share [Abstract]

Schedule of Earnings (Loss) Per Share, Basic and Diluted

The following table sets forth the computation of earnings (loss) per common share and earnings (loss) per common share - assuming dilution:



	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
	(Dollars in thousands, except per share data)
Numerator:
Net income (loss) - numerator for earnings (loss) per common share	$	26,946	$	14,708	$	80,885	$	(30,133	)

Denominator:
Weighted average common shares outstanding (1)	88,897,203		82,516,927		88,772,831		82,322,919
Effect of dilutive securities:
2015 warrants	—		—		—		30,439
Stock options and deferred compensation agreements	850,870		353,052		899,594		422,809
Restricted stock and restricted stock units	364,211		314,158		372,214		296,649
Denominator for earnings (loss) per common share - assuming dilution	90,112,284		83,184,137		90,044,639		83,072,816

Earnings (loss) per common share	$	0.30	$	0.18	$	0.91	$	(0.37	)
Earnings (loss) per common share - assuming dilution	$	0.30	$	0.18	$	0.90	$	(0.37	)


(1)	Weighted average common shares outstanding include shares vested under the NMO Deferred Compensation Plan.

Schedule of Antidilutive Securities Excluded from Computation of Earnings (Loss) Per Share



Period	Number of Shares	Range of Exercise Prices
		Minimum	Maximum
Three months ended June 30, 2017	1,002,391	$24.79	$24.79
Three months ended June 30, 2016	1,061,541	$24.79	$24.79
Six months ended June 30, 2017	1,002,391	$24.79	$24.79
Six months ended June 30, 2016	1,061,541	$24.79	$24.79

Fair Values of Financial Instruments (Narrative) (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($) Basis_Points	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) Basis_Points	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Level 1 to Level 2 transfers, amount	$ 0		$ 0		$ 0
Liabilities, Level 1 to Level 2 transfers, amount	0		0		0
Assets, Level 2 to Level 1 transfers, amount	0		0		0
Liabilities, Level 2 to Level 1 transfers, amount	0		0		$ 0
Assets, transfers into Level 3, amount	0	$ 0	0	$ 0
Liabilities, transfers into Level 3, amount	0	0	0	0
Assets, transfers out of Level 3, amount	0	0	0	0
Liabilities, transfers out of Level 3, amount	$ 0	$ 0	$ 0	$ 0
Fair Value, Sensitivity, Increase in Discount Rate by 10 Percent [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, sensitivity, discount rate adjustment (basis points) \| Basis_Points	100		100
Fixed index annuities embedded derivative, adjustment due to change in discount rate			$ (510,700)
Deferred policy scquisition costs and deferred sales inducements, combined balance, adjustment due to change in discount rate			$ (307,000)
Fair Value, Sensitivity, Decrease in Discount Rate by 10 Percent [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, sensitivity, discount rate adjustment (basis points) \| Basis_Points	100		100
Fixed index annuities embedded derivative, adjustment due to change in discount rate			$ 570,300
Deferred policy scquisition costs and deferred sales inducements, combined balance, adjustment due to change in discount rate			$ 337,700

Fair Values of Financial Instruments (Fair Values and Carrying Amounts of Financial Instruments) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Assets
Held for investment	$ 76,702	$ 68,766
Other investments	314,421	308,774
Coinsurance deposits	4,710,650	4,639,492
Liabilities
Policy benefit reserves	53,903,497	51,637,026
Carrying Amount [Member]
Assets
Available for sale securities	43,893,785	41,060,494
Held for investment	76,931	76,825
Mortgage loans on real estate	2,553,391	2,480,956
Derivative instruments	1,086,624	830,519
Other investments	314,421	308,774
Cash and cash equivalents	1,574,913	791,266
Coinsurance deposits	4,710,650	4,639,492
Counterparty collateral	144,283	145,693
Liabilities
Policy benefit reserves	53,546,680	51,280,331
Single premium immediate annuity (SPIA) benefit reserves	286,856	297,724
Notes and loan payable	888,660	493,755
Subordinated debentures	242,045	241,853
Amounts due under repurchase agreements	61,673	0
Carrying Amount [Member] \| Interest Rate Caps [Member]
Assets
Interest rate derivative assets	468	1,082
Carrying Amount [Member] \| Interest Rate Swap [Member]
Liabilities
Interest rate derivative liabilities	2,001	2,113
Fair Value [Member]
Assets
Available for sale securities	43,893,785	41,060,494
Held for investment	76,702	68,766
Mortgage loans on real estate	2,554,995	2,522,035
Derivative instruments	1,086,624	830,519
Other investments	305,551	300,918
Cash and cash equivalents	1,574,913	791,266
Coinsurance deposits	4,213,996	4,150,792
Counterparty collateral	144,283	145,693
Liabilities
Policy benefit reserves	44,785,605	43,104,183
Single premium immediate annuity (SPIA) benefit reserves	296,948	308,028
Notes and loan payable	929,437	519,440
Subordinated debentures	245,190	225,106
Amounts due under repurchase agreements	61,673	0
Fair Value [Member] \| Interest Rate Caps [Member]
Assets
Interest rate derivative assets	468	1,082
Fair Value [Member] \| Interest Rate Swap [Member]
Liabilities
Interest rate derivative liabilities	$ 2,001	$ 2,113

Fair Values of Financial Instruments (Assumptions Used in Estimating Fair Value) (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Expected cost of annual call options	3.10%	3.10%
Mortality rate assumption	65.00%
Fixed Annuity [Member] \| Minimum [Member] \| Contract Duration (Years), Group 1 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Contract duration (years)	1 year	1 year
Fixed Annuity [Member] \| Minimum [Member] \| Contract Duration (Years), Group 2 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Contract duration (years)	6 years	6 years
Fixed Annuity [Member] \| Minimum [Member] \| Contract Duration (Years), Group 3 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Contract duration (years)	11 years	11 years
Fixed Annuity [Member] \| Minimum [Member] \| Contract Duration (Years), Group 4 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Contract duration (years)	16 years	16 years
Fixed Annuity [Member] \| Minimum [Member] \| Contract Duration (Years), Group 5 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Contract duration (years)	20 years	20 years
Fixed Annuity [Member] \| Maximum [Member] \| Contract Duration (Years), Group 1 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Contract duration (years)	5 years	5 years
Fixed Annuity [Member] \| Maximum [Member] \| Contract Duration (Years), Group 2 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Contract duration (years)	10 years	10 years
Fixed Annuity [Member] \| Maximum [Member] \| Contract Duration (Years), Group 3 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Contract duration (years)	15 years	15 years
Fixed Annuity [Member] \| Maximum [Member] \| Contract Duration (Years), Group 4 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Contract duration (years)	20 years	20 years
Fixed Annuity [Member] \| Average [Member] \| Contract Duration (Years), Group 1 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Average lapse rates	1.95%	1.76%
Average partial withdrawal rates	3.31%	3.30%
Fixed Annuity [Member] \| Average [Member] \| Contract Duration (Years), Group 2 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Average lapse rates	6.85%	6.58%
Average partial withdrawal rates	3.32%	3.30%
Fixed Annuity [Member] \| Average [Member] \| Contract Duration (Years), Group 3 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Average lapse rates	11.28%	11.25%
Average partial withdrawal rates	3.33%	3.32%
Fixed Annuity [Member] \| Average [Member] \| Contract Duration (Years), Group 4 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Average lapse rates	11.99%	12.04%
Average partial withdrawal rates	3.19%	3.18%
Fixed Annuity [Member] \| Average [Member] \| Contract Duration (Years), Group 5 [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Average lapse rates	11.65%	11.68%
Average partial withdrawal rates	3.19%	3.18%

Fair Values of Financial Instruments (Reconciliation of Beginning and Ending Balances of Level 3 Liabilities) (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 7,051,000	$ 6,254,466	$ 6,563,288	$ 5,983,622
Premiums less benefits	497,689	44,632	909,191	135,761
Change in fair value, net	3,676	199,917	79,886	379,632
Ending balance	$ 7,552,365	$ 6,499,015	$ 7,552,365	$ 6,499,015

Investments (Narrative) (Details) $ in Thousands	6 Months Ended
Investments (Narrative) (Details) $ in Thousands	Jun. 30, 2017 USD ($) Securities	Jun. 30, 2016 USD ($)	Dec. 31, 2016 Securities
Investments [Abstract]
Fixed income securities with call features, percentage	37.00%
Fixed income securities with call features, currently callable, percentage	2.10%
Fixed income securities with call features, currently callable, amount	$ 899,100
Fixed income securities with call features, callable during next 12 months, percentage	1.00%
Fixed income securities with call features, callable during next 12 months, amount	$ 409,500
Fixed income securities with call features, not callable until within 6 months of stated maturity, percentage	72.00%
Percentage of fixed maturity portfolio rated investment grade based on NAIC designations	97.00%		97.00%
Number of individual securities with unrealized losses \| Securities	956		1,514
Percentage of unrealized losses on fixed maturity securities where securities are rated investment grade	81.00%		86.00%
Investment Holdings [Line Items]
Scheduled principal repayments, calls and tenders for available for sale securities	$ 970,752	$ 1,421,976
Available For Sale Securities [Member]
Investment Holdings [Line Items]
Proceeds from sales of available for sale securities	376,900	186,100
Fixed Maturity Securities [Member]
Investment Holdings [Line Items]
Scheduled principal repayments, calls and tenders for available for sale securities	$ 593,800	$ 1,200,000

Investments (Schedule of Amortized Cost and Fair Value of Fixed Maturity Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Investment Holdings [Line Items]
Held for investment, amortized cost	$ 76,931	$ 76,825
Held for investment	76,702	68,766
Fixed Maturity Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	41,907,744	39,953,955
Available for sale, gross unrealized gains	2,304,286	1,691,257
Available for sale, gross unrealized losses	(318,245)	(584,718)
Available for sale, fair value	43,893,785	41,060,494
Fixed Maturity Securities [Member] \| United States Government Full Faith and Credit [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	12,114	11,864
Available for sale, gross unrealized gains	228	229
Available for sale, gross unrealized losses	(168)	(288)
Available for sale, fair value	12,174	11,805
Fixed Maturity Securities [Member] \| United States Government Sponsored Agencies [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	1,348,391	1,368,340
Available for sale, gross unrealized gains	30,288	23,360
Available for sale, gross unrealized losses	(37,840)	(46,913)
Available for sale, fair value	1,340,839	1,344,787
Fixed Maturity Securities [Member] \| United States Municipalities, States and Territories [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	3,777,760	3,626,395
Available for sale, gross unrealized gains	369,526	322,948
Available for sale, gross unrealized losses	(9,572)	(22,393)
Available for sale, fair value	4,137,714	3,926,950
Fixed Maturity Securities [Member] \| Foreign Government Obligations [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	228,896	229,589
Available for sale, gross unrealized gains	12,462	11,832
Available for sale, gross unrealized losses	(2,489)	(5,080)
Available for sale, fair value	238,869	236,341
Fixed Maturity Securities [Member] \| Corporate Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	27,813,420	26,333,213
Available for sale, gross unrealized gains	1,656,805	1,149,978
Available for sale, gross unrealized losses	(183,154)	(368,773)
Available for sale, fair value	29,287,071	27,114,418
Held for investment, amortized cost	76,931	76,825
Held for investment, gross unrealized gains	0	0
Held for investment, gross unrealized losses	(229)	(8,059)
Held for investment	76,702	68,766
Fixed Maturity Securities [Member] \| Residential Mortgage Backed Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	1,090,846	1,166,944
Available for sale, gross unrealized gains	93,316	91,445
Available for sale, gross unrealized losses	(2,312)	(3,554)
Available for sale, fair value	1,181,850	1,254,835
Fixed Maturity Securities [Member] \| Commercial Mortgage Backed Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	5,519,767	5,422,255
Available for sale, gross unrealized gains	89,865	59,994
Available for sale, gross unrealized losses	(69,249)	(117,014)
Available for sale, fair value	5,540,383	5,365,235
Fixed Maturity Securities [Member] \| Other Asset Backed Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	2,116,550	1,795,355
Available for sale, gross unrealized gains	51,796	31,471
Available for sale, gross unrealized losses	(13,461)	(20,703)
Available for sale, fair value	2,154,885	1,806,123
Equity Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	7,525	7,521
Available for sale, gross unrealized gains	457	479
Available for sale, gross unrealized losses	0	0
Available for sale, fair value	$ 7,982	$ 8,000

Investments (Fixed Maturity Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis [Abstract]
Available for sale securities, due in one year or less, amortized cost	$ 287,042
Available for sale securities, due after one year through five years, amortized cost	3,482,397
Available for sale securities, due after five years through ten years, amortized cost	11,828,053
Available for sale securities, due after ten years through twenty years, amortized cost	8,981,750
Available for sale securities, due after twenty years, amortized cost	8,601,339
Available for sale securities, securities with a single maturity date, amortized cost	33,180,581
Available for sale securities, amortized cost	41,907,744	$ 39,953,955
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for sale securities, due in one year or less, fair value	294,085
Available for sale securities, due after one year through five years, fair value	3,645,145
Available for sale securities, due after five years through ten years, fair value	12,116,887
Available for sale securities, due after ten years through twenty years, fair value	9,715,165
Available for sale securities, due after twenty years, fair value	9,245,385
Available for sale securities, securities with a single maturity date, fair value	35,016,667
Available for sale securities, fair value	43,893,785	41,060,494
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Held for investment securities, due in one year or less, amortized cost	0
Held for investment securities, due after one year through five years, amortized cost	0
Held for investment securities, due after five years through ten years, amortized cost	0
Held for investment securities, due after ten years through twenty years, amortized cost	0
Held for investment securities, due after twenty years, amortized cost	76,931
Held for investment securities, securities with a single maturity date, amortized cost	76,931
Held for investment, amortized cost	76,931	76,825
Held-to-maturity Securities, Debt Maturities, Fair Value [Abstract]
Held for investment securities, due in one year or less, fair value	0
Held for investment securities, due after one year through five years, fair value	0
Held for investment securities, due after five years through ten years, fair value	0
Held for investment securities, due after ten years through twenty years, fair value	0
Held for investment securities, due after twenty years, fair value	76,702
Held for investment securities, securities with a single maturity date, fair value	76,702
Held for investment	76,702	$ 68,766
Residential Mortgage Backed Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis [Abstract]
Available for sale securities, securities without a single maturity date, amortized cost	1,090,846
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for sale securities, securities without a single maturity date, fair value	1,181,850
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Held for investment securities, securities without a single maturity date, amortized cost	0
Held-to-maturity Securities, Debt Maturities, Fair Value [Abstract]
Held for investment securities, securities without a single maturity date, fair value	0
Commercial Mortgage Backed Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis [Abstract]
Available for sale securities, securities without a single maturity date, amortized cost	5,519,767
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for sale securities, securities without a single maturity date, fair value	5,540,383
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Held for investment securities, securities without a single maturity date, amortized cost	0
Held-to-maturity Securities, Debt Maturities, Fair Value [Abstract]
Held for investment securities, securities without a single maturity date, fair value	0
Other Asset Backed Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis [Abstract]
Available for sale securities, securities without a single maturity date, amortized cost	2,116,550
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for sale securities, securities without a single maturity date, fair value	2,154,885
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Held for investment securities, securities without a single maturity date, amortized cost	0
Held-to-maturity Securities, Debt Maturities, Fair Value [Abstract]
Held for investment securities, securities without a single maturity date, fair value	$ 0

Investments (Net Unrealized Gains on Available for Sale Fixed Maturity Securities and Equity Securities Reported as a Separate Component of Stockholders' Equity) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Investments [Abstract]
Net unrealized gains on available for sale fixed maturity securities and equity securities	$ 1,986,498	$ 1,107,018
Adjustments for assumed changes in amortization of deferred policy acquisition costs and deferred sales inducements	(1,082,516)	(618,661)
Deferred income tax valuation allowance reversal	22,534	22,534
Deferred income tax expense	(316,394)	(170,925)
Net unrealized gains reported as accumulated other comprehensive income	$ 610,122	$ 339,966

Investments (Schedule of Credit Quality of Fixed Maturity Portfolio by NAIC Designation) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Investment Holdings [Line Items]
Amortized cost	$ 41,984,675	$ 40,030,780
Fair value	43,970,487	41,129,260
NAIC, Class 1 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	26,718,443	25,607,268
Fair value	28,144,706	26,507,798
NAIC, Class 2 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	13,907,192	13,037,592
Fair value	14,499,548	13,295,648
NAIC, Class 3 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	1,229,695	1,201,059
Fair value	1,207,581	1,155,702
NAIC, Class 4 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	97,349	154,226
Fair value	89,144	137,188
NAIC, Class 5 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	19,559	17,475
Fair value	20,698	24,664
NAIC, Class 6 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	12,437	13,160
Fair value	$ 8,810	$ 8,260

Investments (Gross Unrealized Losses on Investments, By Category and Length of Time) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	$ 7,273,237	$ 13,195,027
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(201,792)	(454,013)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	1,565,737	1,368,974
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(116,453)	(130,705)
Available for sale securities, continuous unrealized loss position, total, fair value	8,838,974	14,564,001
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(318,245)	(584,718)
United States Government Full Faith and Credit [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	6,867	7,405
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(168)	(288)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	0	0
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	0	0
Available for sale securities, continuous unrealized loss position, total, fair value	6,867	7,405
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(168)	(288)
United States Government Sponsored Agencies [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	945,126	995,548
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(35,343)	(46,913)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	49,503	0
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(2,497)	0
Available for sale securities, continuous unrealized loss position, total, fair value	994,629	995,548
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(37,840)	(46,913)
United States Municipalities, States and Territories [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	273,302	463,409
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(9,572)	(22,393)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	0	0
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	0	0
Available for sale securities, continuous unrealized loss position, total, fair value	273,302	463,409
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(9,572)	(22,393)
Foreign Government Obligations [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	0	29,158
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	0	(913)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	11,844	20,388
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(2,489)	(4,167)
Available for sale securities, continuous unrealized loss position, total, fair value	11,844	49,546
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(2,489)	(5,080)
Corporate Securities [Member] \| Finance, Insurance and Real Estate Sectors [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	1,132,134	1,940,107
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(37,599)	(70,421)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	86,335	82,907
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(1,495)	(7,723)
Available for sale securities, continuous unrealized loss position, total, fair value	1,218,469	2,023,014
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(39,094)	(78,144)
Corporate Securities [Member] \| Manufacturing, Construction and Mining [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	458,458	1,199,420
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(9,156)	(34,304)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	200,709	311,591
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(13,648)	(23,273)
Available for sale securities, continuous unrealized loss position, total, fair value	659,167	1,511,011
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(22,804)	(57,577)
Corporate Securities [Member] \| Utilities and Related Sectors [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	523,863	1,401,650
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(14,319)	(45,015)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	43,553	58,597
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(2,612)	(5,820)
Available for sale securities, continuous unrealized loss position, total, fair value	567,416	1,460,247
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(16,931)	(50,835)
Corporate Securities [Member] \| Wholesale/Retail Trade [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	282,589	637,121
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(9,583)	(18,880)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	42,120	29,719
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(4,812)	(1,930)
Available for sale securities, continuous unrealized loss position, total, fair value	324,709	666,840
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(14,395)	(20,810)
Corporate Securities [Member] \| Services, Media and Other [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	1,156,695	2,539,519
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(33,573)	(82,196)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	619,260	716,857
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(56,357)	(79,211)
Available for sale securities, continuous unrealized loss position, total, fair value	1,775,955	3,256,376
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(89,930)	(161,407)
Corporate Securities [Member] \| Insurance [Member]
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held for investment securities, continuous unrealized loss position, less than 12 months, fair value	0	0
Held for investment securities, continuous unrealized loss position, less than 12 months, unrealized losses	0	0
Held for investment securities, continuous unrealized loss position, 12 months or longer, fair value	76,702	68,766
Held for investment securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(229)	(8,059)
Held for investment securities, continuous unrealized loss position, total, fair value	76,702	68,766
Held for investment securities, continuous unrealized loss position, total, unrealized losses	(229)	(8,059)
Residential Mortgage Backed Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	40,684	81,762
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(1,631)	(3,463)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	8,036	1,853
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(681)	(91)
Available for sale securities, continuous unrealized loss position, total, fair value	48,720	83,615
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(2,312)	(3,554)
Commercial Mortgage Backed Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	1,924,949	3,148,395
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(44,461)	(116,938)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	439,081	895
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(24,788)	(76)
Available for sale securities, continuous unrealized loss position, total, fair value	2,364,030	3,149,290
Available for sale securities, continuous unrealized loss position, total, unrealized losses	(69,249)	(117,014)
Other Asset Backed Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	528,570	751,533
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	(6,387)	(12,289)
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	65,296	146,167
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	(7,074)	(8,414)
Available for sale securities, continuous unrealized loss position, total, fair value	593,866	897,700
Available for sale securities, continuous unrealized loss position, total, unrealized losses	$ (13,461)	$ (20,703)

Investments (Changes in Net Unrealized Gains on Investments) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Investment Holdings [Line Items]
Fixed maturity securities held for investment carried at amortized cost	$ 9,806	$ 820	$ 7,830	$ 3,065
Investments carried at fair value, available for sale	598,399	1,167,860	879,480	2,282,928
Adjustment for effect on other balance sheet accounts:
Deferred policy acquisition costs and deferred sales inducements	(312,893)	(609,224)	(463,855)	(1,218,975)
Deferred income tax asset/liability	(99,927)	(195,523)	(145,469)	(372,384)
Total adjustment for effect on other balance sheet accounts	(412,820)	(804,747)	(609,324)	(1,591,359)
Change in net unrealized gains on investments carried at fair value	185,579	363,113	270,156	691,569
Fixed Maturity Securities [Member]
Investment Holdings [Line Items]
Investments carried at fair value, available for sale	598,408	1,167,861	879,502	2,282,946
Equity Securities [Member]
Investment Holdings [Line Items]
Investments carried at fair value, available for sale	$ (9)	$ (1)	$ (22)	$ (18)

Investments (Net Realized Gains (Losses) on Invesments, Excluding Other Than Temporary Impairments) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Gain (Loss) on Investments [Line Items]
Net realized gains (losses) on investments, excluding other than temporary impairment (OTTI) losses	$ 3,873	$ 2,737	$ 6,211	$ 5,424
Fixed Maturity Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross realized gains	4,479	4,604	10,051	6,091
Gross realized losses	(899)	(1,368)	(4,462)	(2,599)
Gross realized gains (losses), excluding other than temporary impairments	3,580	3,236	5,589	3,492
Other Investments [Member]
Gain (Loss) on Investments [Line Items]
Gain on sale of real estate	15	705	44	836
Loss on sale of real estate	0	(1)	0	(93)
Gain (loss) on other investments	15	704	44	743
Mortgage Loans on Real Estate [Member]
Gain (Loss) on Investments [Line Items]
Decrease (increase) in allowance for credit losses	278	(2,885)	578	(3,833)
Recovery of specific allowance	0	1,682	0	5,022
Change in allowance for credit losses and recoveries	$ 278	$ (1,203)	$ 578	$ 1,189

Investments (Significant Assumptions in Determining Credit Loss Component of Other Than Temporary Impairment on Residential Mortgage Backed Securities) (Details) - Residential Mortgage Backed Securities [Member]	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Prime Sector [Member] \| Vintage Year 2005 [Member] \| Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate	7.50%	7.70%
Default rate	8.00%	14.00%
Loss severity	45.00%	50.00%
Prime Sector [Member] \| Vintage Year 2005 [Member] \| Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate	7.70%	7.70%
Default rate	16.00%	14.00%
Loss severity	50.00%	50.00%
Prime Sector [Member] \| Vintage Year 2006 [Member] \| Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate		7.30%
Default rate		13.00%
Loss severity		50.00%
Prime Sector [Member] \| Vintage Year 2006 [Member] \| Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate		7.30%
Default rate		13.00%
Loss severity		50.00%
Prime Sector [Member] \| Vintage Year 2007 [Member] \| Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate	6.20%	6.20%
Default rate	15.00%	18.00%
Loss severity	50.00%	50.00%
Prime Sector [Member] \| Vintage Year 2007 [Member] \| Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate	6.60%	6.40%
Default rate	19.00%	31.00%
Loss severity	60.00%	55.00%
Alt-A Sector [Member] \| Vintage Year 2005 [Member] \| Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate		7.40%
Default rate		11.00%
Loss severity		60.00%
Alt-A Sector [Member] \| Vintage Year 2005 [Member] \| Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate		7.40%
Default rate		11.00%
Loss severity		60.00%

Investments (Other Than Temporary Impairments by Asset Type) (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($) Securities	Jun. 30, 2016 USD ($) Securities	Jun. 30, 2017 USD ($) Securities	Jun. 30, 2016 USD ($) Securities
Other than Temporary Impairment Losses, Investments [Abstract]
Other than temporary impairment, number of securities \| Securities	3	5	6	16
Total OTTI losses	$ 0	$ (762)	$ 0	$ (6,780)
Portion of OTTI losses recognized from other comprehensive income	(949)	(3,684)	(1,090)	(3,360)
Net OTTI losses recognized in operations	$ (949)	$ (4,446)	$ (1,090)	$ (10,140)
Corporate Securities [Member] \| Energy [Member]
Other than Temporary Impairment Losses, Investments [Abstract]
Other than temporary impairment, number of securities \| Securities				2
Total OTTI losses				$ (642)
Portion of OTTI losses recognized from other comprehensive income				0
Net OTTI losses recognized in operations				$ (642)
Corporate Securities [Member] \| Telecommunications [Member]
Other than Temporary Impairment Losses, Investments [Abstract]
Other than temporary impairment, number of securities \| Securities				1
Total OTTI losses				$ (4,462)
Portion of OTTI losses recognized from other comprehensive income				562
Net OTTI losses recognized in operations				$ (3,900)
Corporate Securities [Member] \| Utilities [Member]
Other than Temporary Impairment Losses, Investments [Abstract]
Other than temporary impairment, number of securities \| Securities				1
Total OTTI losses				$ (136)
Portion of OTTI losses recognized from other comprehensive income				0
Net OTTI losses recognized in operations				$ (136)
Residential Mortgage Backed Securities [Member]
Other than Temporary Impairment Losses, Investments [Abstract]
Other than temporary impairment, number of securities \| Securities	2	2	5	6
Total OTTI losses	$ 0	$ 0	$ 0	$ 0
Portion of OTTI losses recognized from other comprehensive income	(662)	(202)	(803)	(440)
Net OTTI losses recognized in operations	$ (662)	$ (202)	$ (803)	$ (440)
Commercial Mortgage Backed Securities [Member]
Other than Temporary Impairment Losses, Investments [Abstract]
Other than temporary impairment, number of securities \| Securities		2		5
Total OTTI losses		$ (762)		$ (1,540)
Portion of OTTI losses recognized from other comprehensive income		0		0
Net OTTI losses recognized in operations		$ (762)		$ (1,540)
Other Asset Backed Securities [Member]
Other than Temporary Impairment Losses, Investments [Abstract]
Other than temporary impairment, number of securities \| Securities	1	1	1	1
Total OTTI losses	$ 0	$ 0	$ 0	$ 0
Portion of OTTI losses recognized from other comprehensive income	(287)	(3,482)	(287)	(3,482)
Net OTTI losses recognized in operations	$ (287)	$ (3,482)	$ (287)	$ (3,482)

Investments (Cumulative Credit Loss Portion of Other Than Temporary Impairment Recognized in Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Investments [Abstract]
Cumulative credit loss at beginning of period	$ (152,577)	$ (151,518)	$ (166,375)	$ (145,824)
Credit losses on securities for which OTTI has not previously been recognized	0	(762)	0	(6,218)
Additional credit losses on securities for which OTTI has previously been recognized	(949)	(3,684)	(1,090)	(3,922)
Accumulated losses on securities that were disposed of during the period	0	1,556	13,939	1,556
Cumulative credit loss at end of period	$ (153,526)	$ (154,408)	$ (153,526)	$ (154,408)

Investments (Cumulative Noncredit Portion of Other Than Temporary Impairment Recognized in Other Comprehensive Income and Change in Fair Value Since Other Than Temporary Impairment) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Investment Holdings [Line Items]
Amortized cost	$ 342,457	$ 399,690
OTTI recognized in other comprehensive income	(174,756)	(177,494)
Change in fair value since OTTI was recognized	211,891	217,747
Fair value	379,592	439,943
Corporate Securities [Member]
Investment Holdings [Line Items]
Amortized cost	10,502	17,549
OTTI recognized in other comprehensive income	(4,263)	(5,910)
Change in fair value since OTTI was recognized	9,231	13,566
Fair value	15,470	25,205
Residential Mortgage Backed Securities [Member]
Investment Holdings [Line Items]
Amortized cost	327,388	368,862
OTTI recognized in other comprehensive income	(169,137)	(169,941)
Change in fair value since OTTI was recognized	204,438	205,854
Fair value	362,689	404,775
Commercial Mortgage Backed Securities [Member]
Investment Holdings [Line Items]
Amortized cost		6,596
OTTI recognized in other comprehensive income		0
Change in fair value since OTTI was recognized		(107)
Fair value		6,489
Other Asset Backed Securities [Member]
Investment Holdings [Line Items]
Amortized cost	4,567	6,683
OTTI recognized in other comprehensive income	(1,356)	(1,643)
Change in fair value since OTTI was recognized	(1,778)	(1,566)
Fair value	$ 1,433	$ 3,474

Mortgage Loans on Real Estate (Narrative) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($) portfolio_segment	Dec. 31, 2016 USD ($)
Mortgage Loans on Real Estate [Abstract]
Number of portfolio segments that make up financing receivables \| portfolio_segment	1
Impaired mortgage loans, workout terms, interest only payments, six month terms	6 months
Impaired mortgage loans, workout terms, interest only payments, twelve month terms	12 months
Impaired mortgage loans, workout terms, cash flow sweep, number of months	12 months
Number of days past due, non-accrual status	90 days
Outstanding principal of loans in a non-accrual status	$ 2,200	$ 0
Minimum [Member]
Mortgage Loans on Real Estate [Line Items]
Number of days past due, delinquent status	60 days
Commercial Real Estate Portfolio Segment [Member]
Mortgage Loans on Real Estate [Line Items]
Commitments outstanding	$ 46,900

Mortgage Loans on Real Estate (Summary of Mortgage Loan Portfolio) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Mortgage Loans on Real Estate [Abstract]
Principal outstanding	$ 2,562,449	$ 2,490,619
Loan loss allowance	(7,849)	(8,427)
Deferred prepayment fees	(1,209)	(1,236)
Mortgage loans on real estate	$ 2,553,391	$ 2,480,956

Mortgage Loans on Real Estate (Mortgage Loan Portfolio Summarized by Geographic Region and Property Type) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 2,562,449	$ 2,490,619
Percent	100.00%	100.00%
East [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 596,587	$ 635,434
Percent	23.30%	25.50%
Middle Atlantic [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 155,234	$ 151,640
Percent	6.10%	6.10%
Mountain [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 302,764	$ 235,932
Percent	11.80%	9.50%
New England [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 12,496	$ 12,724
Percent	0.50%	0.50%
Pacific [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 423,086	$ 385,683
Percent	16.50%	15.50%
South Atlantic [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 542,146	$ 519,065
Percent	21.20%	20.80%
West North Central [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 311,126	$ 325,447
Percent	12.10%	13.10%
West South Central [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 219,010	$ 224,694
Percent	8.50%	9.00%
Office [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 291,118	$ 308,578
Percent	11.40%	12.40%
Medical Office [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 35,248	$ 50,780
Percent	1.40%	2.10%
Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 989,810	$ 886,942
Percent	38.60%	35.60%
Industrial/Warehouse [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 691,630	$ 700,644
Percent	27.00%	28.10%
Apartment [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 377,170	$ 375,837
Percent	14.70%	15.10%
Mixed Use/Other [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 177,473	$ 167,838
Percent	6.90%	6.70%

Mortgage Loans on Real Estate (Allowance for Loan Losses Rollforward) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning allowance balance			$ (8,427)
Ending allowance balance	$ (7,849)		(7,849)
Specific Allowance [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning allowance balance	(1,327)	$ (5,750)	(1,327)	$ (7,842)
Charge-offs	0	2,101	0	2,101
Recoveries	0	1,682	0	5,022
Change in provision for credit losses	(722)	(2,585)	(722)	(3,833)
Ending allowance balance	(2,049)	(4,552)	(2,049)	(4,552)
General Allowance [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning allowance balance	(6,800)	(6,000)	(7,100)	(6,300)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Change in provision for credit losses	1,000	(300)	1,300	0
Ending allowance balance	$ (5,800)	$ (6,300)	$ (5,800)	$ (6,300)

Mortgage Loans on Real Estate (Impaired Mortgage Loans on Real Estate by Basis of Impairment) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Mortgage Loans on Real Estate [Abstract]
Individually evaluated for impairment	$ 6,773	$ 4,640
Collectively evaluated for impairment	2,555,676	2,485,979
Principal outstanding	$ 2,562,449	$ 2,490,619

Mortgage Loans on Real Estate (Real Estate Owned) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2016	Jun. 30, 2017
Mortgage Loans on Real Estate [Abstract]
Real estate owned at beginning of period	$ 5,356	$ 6,485
Real estate acquired in satisfaction of mortgage loans	0	0
Additions	0	0
Sales	(5,338)	(6,444)
Impairments	0	0
Depreciation	(18)	(41)
Real estate owned at end of period	0	0
Real estate owned at end of period	$ 5,356	$ 6,485	$ 0

Mortgage Loans on Real Estate (Mortgage Loans by Credit Quality Indicator) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Mortgage Loans on Real Estate [Abstract]
Performing	$ 2,558,711	$ 2,489,028
In workout	1,516	1,591
Delinquent	0	0
Collateral dependent	2,222	0
Principal outstanding	$ 2,562,449	$ 2,490,619

Mortgage Loans on Real Estate (Schedule of Financing Receivables Past Due) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Commercial mortgage loans, past due	$ 0	$ 2,737
Commercial mortgage loans, current	2,560,227	2,487,882
Commercial mortgage loans, collateral dependent receivables	2,222	0
Principal outstanding	2,562,449	2,490,619
30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Commercial mortgage loans, past due	0	2,737
60 to 89 Days [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Commercial mortgage loans, past due	0	0
90 Days and Over [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Commercial mortgage loans, past due	$ 0	$ 0

Mortgage Loans on Real Estate (Schedule of Impaired Financing Receivables) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Mortgage loans with an allowance, recorded investment	$ 4,724		$ 4,724		$ 3,313
Mortgage loans with no related allowance, recorded investment	1,516		1,516		1,591
Impaired mortgage loans, recorded investment	6,240		6,240		4,904
Mortgage loans with an allowance, unpaid principal balance	6,773		6,773		4,640
Mortgage loans with no related allowance, unpaid principal balance	1,516		1,516		1,591
Impaired mortgage loans, unpaid principal balance	8,289		8,289		6,231
Mortgage loans with an allowance, related allowance	(2,049)		(2,049)		$ (1,327)
Mortgage loans with an allowance, average recorded investment	5,107	$ 6,921	5,135	$ 7,166
Mortgage loans with no related allowance, average recorded investment	1,535	4,737	1,553	4,793
Impaired mortgage loans, average recorded investment	6,642	11,658	6,688	11,959
Mortgage loans with an allowance, interest income recognized	104	164	207	329
Mortgage loans with no related allowance, interest income recognized	23	74	46	150
Impaired mortgage loans, interest income reoognized	$ 127	$ 238	$ 253	$ 479

Mortgage Loans on Real Estate (Troubled Debt Restructurings) (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017 USD ($) loans	Dec. 31, 2016 USD ($) loans
Financing Receivable, Modifications [Line Items]
Number of TDRs \| loans	2	2
Principal balance outstanding	$ 4,955	$ 5,024
Specific loan loss allowance	(467)	(467)
Net carrying amount	$ 4,488	$ 4,557
South Atlantic [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs \| loans	1	1
Principal balance outstanding	$ 2,978	$ 3,004
Specific loan loss allowance	0	0
Net carrying amount	$ 2,978	$ 3,004
East North Central [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs \| loans	1	1
Principal balance outstanding	$ 1,977	$ 2,020
Specific loan loss allowance	(467)	(467)
Net carrying amount	$ 1,510	$ 1,553

Derivative Instruments (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Derivative collateral	$ 1,100.0	$ 800.0
Credit risk, maximum exposure	$ 16.9	$ 55.5
Call Options [Member]
Derivative [Line Items]
Investment maturity period	1 year
SunTrust [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Collateral on deposit	$ 1.8
SunTrust [Member] \| Not Designated as Hedging Instrument [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Derivative [Line Items]
Derivative, cap interest rate	2.50%
Interest Rate Swap [Member] \| SunTrust [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, term of contract	7 years
Interest Rate Caps [Member] \| SunTrust [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, term of contract	7 years

Derivative Instruments (Fair Value of Derivative Instruments as Presented in the Consolidated Balance Sheets) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative assets	$ 1,086,624	$ 830,519
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	1,087,092	831,601
Derivative liabilities	7,554,366	6,565,401
Call Options [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	1,086,624	830,519
Interest Rate Caps [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	468	1,082
Fixed Index Annuities - Embedded Derivatives [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	7,552,365	6,563,288
Interest Rate Swap [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 2,001	$ 2,113

Derivative Instruments (Change in Fair Value of Derivatives Included in the Consolidated Statement of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of derivatives	$ 266,820	$ 39,099	$ 653,353	$ (34,966)
Change in fair value of embedded derivatives	174,973	284,303	399,143	550,160
Call Options [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of derivatives	267,705	40,394	654,441	(30,357)
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of derivatives	(549)	(982)	(474)	(3,626)
Interest Rate Caps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of derivatives	(336)	(313)	(614)	(983)
Fixed Index Annuities - Embedded Derivatives [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of embedded derivatives	3,676	199,917	79,886	379,632
Other Changes in Difference Between Policy Benefit Reserves Computed Using Derivative Accounting Vs. Long-Duration Contracts Accounting [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of embedded derivatives	$ 171,297	$ 84,386	$ 319,257	$ 170,528

Derivative Instruments (Derivative Call Options, Notional Amount and Fair Value, by Counterparty) (Details) - Call Options [Member] - Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Notional amount	$ 33,259,347	$ 31,048,082
Derivative instruments	1,086,624	830,519
Bank of America [Member]
Derivative [Line Items]
Notional amount	5,020,592	5,958,884
Derivative instruments	179,048	178,477
Barclays [Member]
Derivative [Line Items]
Notional amount	3,760,675	3,441,832
Derivative instruments	103,317	89,721
BNP Paribas [Member]
Derivative [Line Items]
Notional amount	1,837,242	1,199,265
Derivative instruments	48,330	19,598
Citibank, N.A. [Member]
Derivative [Line Items]
Notional amount	3,791,993	4,038,528
Derivative instruments	155,815	97,094
Credit Suisse [Member]
Derivative [Line Items]
Notional amount	3,721,586	2,130,710
Derivative instruments	92,577	44,242
Deutsche Bank [Member]
Derivative [Line Items]
Notional amount	0	25,935
Derivative instruments	0	892
J.P. Morgan [Member]
Derivative [Line Items]
Notional amount	1,622,559	1,785,583
Derivative instruments	53,359	19,645
Morgan Stanley [Member]
Derivative [Line Items]
Notional amount	2,795,503	2,543,421
Derivative instruments	104,024	64,425
Royal Bank of Canada [Member]
Derivative [Line Items]
Notional amount	3,167,888	3,384,310
Derivative instruments	104,644	103,510
SunTrust [Member]
Derivative [Line Items]
Notional amount	3,147,079	2,375,418
Derivative instruments	101,690	72,990
Wells Fargo [Member]
Derivative [Line Items]
Notional amount	3,986,928	3,850,842
Derivative instruments	131,676	130,545
Exchange Traded [Member]
Derivative [Line Items]
Notional amount	407,302	313,354
Derivative instruments	$ 12,144	$ 9,380

Derivative Instruments (Interest Rate Swap) (Details) - Interest Rate Swap, Maturity Date, March 15, 2021, 2.415% [Member] - Interest Rate Swap [Member] - SunTrust [Member] - Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Notional amount	$ 85,500
Pay rate	2.415%
Derivative liabilities	$ (2,001)	$ (2,113)

Derivative Instruments (Interest Rate Caps) (Details) - Interest Rate Caps [Member] - SunTrust [Member] - Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Notional amount	$ 79,000
Derivative assets	468	$ 1,082
Interest Rate Caps, Maturity Date, July 7, 2021, 2.50% [Member]
Derivative [Line Items]
Notional amount	$ 40,000
Cap rate	2.50%
Derivative assets	$ 233	542
Interest Rate Caps, Maturity Date, July 8, 2021, 2.50% [Member]
Derivative [Line Items]
Notional amount	$ 12,000
Cap rate	2.50%
Derivative assets	$ 70	163
Interest Rate Caps, Maturity Date, July 29, 2021, 2.50% [Member]
Derivative [Line Items]
Notional amount	$ 27,000
Cap rate	2.50%
Derivative assets	$ 165	$ 377

Notes and Loan Payable and Amounts Due Under Repurchase Agreements (Schedule of Notes and Loan Payable) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Jun. 16, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Notes and loan payable	$ 888,660		$ 493,755
July 2021 Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	400,000		400,000
Unamortized debt issue costs	(5,187)		(5,733)
June 2027 Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	500,000	$ 500,000	0
Unamortized debt issue costs	(5,804)		0
Unamortized discount	(349)	$ (300)	0
Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	0		100,000
Unamortized debt issue costs	$ 0		$ (512)

Notes and Loan Payable and Amounts Due Under Repurchase Agreements (2027 Notes Narrative) (Details) - USD ($) $ in Thousands	Jul. 17, 2017	Jun. 16, 2017	Jun. 30, 2017	Dec. 31, 2016
June 2027 Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 500,000	$ 500,000	$ 0
Interest rate		5.00%
Unamortized discount		$ 300	$ 349	$ 0
Debt financing costs		5,800
Term Loan [Member]
Debt Instrument [Line Items]
Extinguishment of debt, amount		$ 100,000
Subsequent Event [Member] \| July 2021 Notes [Member]
Debt Instrument [Line Items]
Extinguishment of debt, amount	$ 400,000

Notes and Loan Payable and Amounts Due Under Repurchase Agreements (Repurchase Agreements Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Debt Disclosure [Abstract]
Repurchase agreement, average borrowings	$ 36,100	$ 0	$ 69,100	$ 0
Repurchase agreement, maximum amount borrowed			$ 274,500
Repurchase agreement, weighted average interest rate	1.02%		0.74%

Earnings (Loss) Per Share and Stockholders' Equity (Schedule of Earnings (Loss) Per Share, Basic and Diluted) (Details) - USD ($)
$ / shares in Units, $ in Thousands

3 Months Ended

6 Months Ended

Jun. 30, 2017

Jun. 30, 2016

Jun. 30, 2017

Jun. 30, 2016

Earnings Per Share, Basic and Diluted [Line Items]

Net income (loss) - numerator for earnings (loss) per common share

$ 26,946

$ 14,708

$ 80,885

$ (30,133)

Weighted average common shares outstanding (shares)

^[1]

88,897,203

82,516,927

88,772,831

82,322,919

Effect of dilutive securities: 2015 warrants (shares)

30,439

Denominator for earnings (loss) per common share - assuming dilution (shares)

90,112,284

83,184,137

90,044,639

83,072,816

Earnings (loss) per common share

$ 0.30

$ 0.18

$ 0.91

$ (0.37)

Earnings (loss) per common share - assuming dilution

$ 0.30

$ 0.18

$ 0.90

$ (0.37)

Stock Options and Deferred Compensation Agreements [Member]

Earnings Per Share, Basic and Diluted [Line Items]

Effect of dilutive securities: share-based payment arrangements (shares)

850,870

353,052

899,594

422,809

Restricted Stock and Restricted Stock Units [Member]

Earnings Per Share, Basic and Diluted [Line Items]

Effect of dilutive securities: share-based payment arrangements (shares)

364,211

314,158

372,214

296,649

[1]	Weighted average common shares outstanding include shares vested under the NMO Deferred Compensation Plan.

Earnings (Loss) Per Share and Stockholders' Equity (Schedule of Antidilutive Securities Excluded from Computation of Earnings (Loss) Per Share) (Details) - Stock Options [Member] - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares	1,002,391	1,061,541	1,002,391	1,061,541
Minimum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Range of exercise prices	$ 24.79	$ 24.79	$ 24.79	$ 24.79
Maximum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Range of exercise prices	$ 24.79	$ 24.79	$ 24.79	$ 24.79

Earnings (Loss) Per Share and Stockholders' Equity (Stockholders' Equity Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	6 Months Ended
	Aug. 01, 2016	Aug. 31, 2015	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Public offering related to equity forward transaction, shares		8,600,000
Forward rate per share		$ 25.25
Shares subject to forward sale agreement		4,300,000
Optional shares available to underwriters		1,290,000
Shares of common stock issued	5,590,000
Proceeds from issuance of common stock	$ 134,700		$ 4,618	$ 3,779

Subsequent Events (Narrative) (Details) - USD ($) $ in Thousands		6 Months Ended
	Jul. 17, 2017	Jun. 30, 2017	Jun. 30, 2016
Subsequent Event [Line Items]
Loss on extinguishment of debt		$ (428)	$ 0
July 2021 Notes [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Extinguishment of debt, cash paid	$ 413,300
Debt instrument, redemption price, percentage	3.313%
Extinguishment of debt, amount	$ 400,000
Loss on extinguishment of debt	$ (18,400)

Subsequent Events	6 Months Ended
Subsequent Events	Jun. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events As discussed in Note 6, we used a portion of the net proceeds from the issuance of the 2027 Notes to redeem our 2021 Notes on July 17, 2017. We paid $413.3 million to redeem the 2021 Notes which included a redemption premium equal to 3.313% of the $400 million principal amount of the 2021 Notes. We incurred a loss of $18.4 million on the redemption of the 2021 Notes.

Commitments and Contingencies (Narrative) (Details) $ in Millions	Jun. 30, 2017 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Unfunded commitments to limited partnerships	$ 58.2
Unfunded commitments to secured bank loans	$ 9.3

Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New accounting pronouncement, effect of adoption, quantification	$ 0.3	$ 1.6