American National (ANG-PB) 10-Q 7 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information Document	3 Months Ended
	Mar. 31, 2015	Apr. 30, 2015
Document Information [Line Items]
Entity Registrant Name	AMERICAN EQUITY INVESTMENT LIFE HOLDING CO
Entity Central Index Key	1039828
Document Type	10-Q
Document Period End Date	31-Mar-15
Amendment Flag	FALSE
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	-19
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		77,057,850

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Fixed maturity securities:
Available for sale, at fair value (amortized cost: 2015 - $31,443,319; 2014 - $30,205,046)	$34,203,641	$32,445,202
Held for investment, at amortized cost (fair value: 2015 - $82,984; 2014 - $75,838)	76,479	76,432
Equity securities, available for sale, at fair value (cost: 2015 - $7,511; 2014 - $7,509)	7,849	7,805
Mortgage loans on real estate	2,433,757	2,434,580
Derivative instruments	610,764	731,113
Other investments	285,177	286,726
Total investments	37,617,667	35,981,858
Cash and cash equivalents	293,764	701,514
Coinsurance deposits	3,101,783	3,044,342
Accrued investment income	358,241	326,559
Deferred policy acquisition costs	2,021,990	2,058,556
Deferred sales inducements	1,558,921	1,587,257
Income taxes recoverable	0	9,252
Other assets	436,349	280,396
Total assets	45,388,715	43,989,734
Liabilities:
Policy benefit reserves	41,037,401	39,802,861
Other policy funds and contract claims	353,741	365,819
Notes payable	421,919	421,679
Subordinated debentures	246,293	246,243
Amounts due under repurchase agreements	15,075	0
Deferred income taxes	74,149	3,895
Income taxes payable	13,290	0
Other liabilities	900,127	1,009,361
Total liabilities	43,061,995	41,849,858
Stockholders' equity:
Preferred stock, par value $1 per share, 2,000,000 shares authorized, 2014 and 2013 - no shares issued and outstanding	0	0
Common stock, par value $1 per share, 200,000,000 shares authorized; issued and outstanding: 2015 - 76,681,287 shares (excluding 3,685,784 treasury shares); 2014 - 76,062,407 shares (excluding 4,126,167 treasury shares)	76,681	76,062
Additional paid-in capital	521,203	513,218
Accumulated other comprehensive income	893,738	721,401
Retained earnings	835,098	829,195
Total stockholders' equity	2,326,720	2,139,876
Total liabilities and stockholders' equity	$45,388,715	$43,989,734

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parentheticals) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, except Share data, unless otherwise specified
Fixed maturity securities:
Available for sale, at fair value, amortized cost	$31,443,319	$30,205,046
Held for investment, at amortized cost, fair value	82,984	75,838
Equity securities, available for sale, at fair value, cost	$7,511	$7,509
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	76,681,287	76,062,407
Common stock, shares outstanding	76,681,287	76,062,407
Common stock, shares held in treasury	3,685,784	4,126,167

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Revenues:
Premiums and other considerations	$6,997		$7,331
Annuity product charges	28,682		25,272
Net investment income	399,669		370,005
Change in fair value of derivatives	-31,100		48,493
Net realized gains (losses) on investments, excluding other than temporary impairment (OTTI) losses	4,879		-714
OTTI losses on investments:
Total OTTI losses	-132		0
Portion of OTTI losses recognized from other comprehensive income	0		-905
Net OTTI losses recognized in operations	-132		-905
Loss on extinguishment of debt	0		-3,977
Total revenues	408,995		445,505
Benefits and expenses:
Insurance policy benefits and change in future policy benefits	9,220		10,095
Interest sensitive and index product benefits	282,825		317,192
Amortization of deferred sales inducements	10,953		666
Change in fair value of embedded derivatives	51,213		92,619
Interest expense on notes payable	7,339		10,264
Interest expense on subordinated debentures	3,016		3,008
Amortization of deferred policy acquisition costs	14,286		7,194
Other operating costs and expenses	21,122		19,085
Total benefits and expenses	399,974		460,123
Income (loss) before income taxes	9,021		-14,618
Income tax expense (benefit)	3,118		-4,865
Net income (loss)	$5,903		($9,753)
Earnings (loss) per common share	$0.08		($0.13)
Earnings (loss) per common share - assuming dilution	$0.07		($0.13)
Weighted average common shares outstanding: earnings (loss) per common share	77,041,704	[1]	72,518,574	[1]
Weighted average common shares outstanding: earnings (loss) per common share - assuming dilution	79,118,034		79,615,779
[1]	Weighted average common shares outstanding include shares vested under the NMO Deferred Compensation Plan and exclude unallocated shares held by the ESOP.

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Net income (loss)	$5,903		($9,753)
Other comprehensive income:
Change in net unrealized investment gains/losses (1)	264,113	[1]	440,688	[1]
Noncredit component of OTTI losses (1)	0	[1]	408	[1]
Reclassification of unrealized investment gains/losses to net income (1)	1,019	[1]	-730	[1]
Other comprehensive income before income tax	265,132		440,366
Income tax effect related to other comprehensive income	-92,795		-154,127
Other comprehensive income	172,337		286,239
Comprehensive income	$178,240		$276,486
[1]	Net of related adjustments to amortization of deferred sales inducements and deferred policy acquisition costs.

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Stockholders' Equity (USD $)	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Unallocated Common Stock Held By ESOP [Member]	Accumulated Other Comprehensive Income [Member]	Retained Earnings [Member]
In Thousands, unless otherwise specified
Stockholders' equity at beginning of period at Dec. 31, 2013	$1,384,687	$70,535	$550,400	($631)	$46,196	$718,187
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	-9,753					-9,753
Other comprehensive income	286,239				286,239
Allocation of common stock by ESOP, including excess income tax benefits	682		364	318
Share-based compensation, including excess income tax benefits	2,578		2,578
Issuance of common stock under compensation plans, including excess income tax benefits	6,639	908	5,731
Extinguishment of convertible senior notes, net of tax, including shares of common stock issued upon conversion	-16,123	947	-17,070
Stockholders' equity at end of period at Mar. 31, 2014	1,654,949	72,390	542,003	-313	332,435	708,434
Stockholders' equity at beginning of period at Dec. 31, 2014	2,139,876	76,062	513,218	0	721,401	829,195
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	5,903					5,903
Other comprehensive income	172,337				172,337
Share-based compensation, including excess income tax benefits	4,515		4,515
Issuance of common stock under compensation plans, including excess income tax benefits	4,089	619	3,470
Stockholders' equity at end of period at Mar. 31, 2015	$2,326,720	$76,681	$521,203	$0	$893,738	$835,098

Consolidated_Statements_of_Cha1

Consolidated Statements of Changes in Stockholders' Equity (Parentheticals)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Shares of common stock allocated by ESOP, including excess income tax benefits		29,309
Shares of common stock issued under compensation plans, including excess income tax benefits	618,880	908,032
Shares of common stock issued upon extinguishment of convertible senior notes		946,793

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Operating activities
Net income (loss)	$5,903	($9,753)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Interest sensitive and index product benefits	282,825	317,192
Amortization of deferred sales inducements	10,953	666
Annuity product charges	-28,682	-25,272
Change in fair value of embedded derivatives	51,213	92,619
Decrease in traditional life and accident and health insurance reserves	-868	-91
Policy acquisition costs deferred	-121,822	-93,333
Amortization of deferred policy acquisition costs	14,286	7,194
Provision for depreciation and other amortization	1,267	3,000
Amortization of discounts and premiums on investments	-1,428	-2,829
Realized gains/losses on investments and net OTTI losses recognized in operations	-4,747	1,619
Change in fair value of derivatives	30,636	-48,493
Deferred income taxes	-22,541	-37,360
Loss on extinguishment of debt	0	3,977
Share-based compensation	1,687	37
Change in accrued investment income	-31,682	-21,177
Change in income taxes recoverable/payable	22,542	7,909
Change in other assets	-918	-339
Change in other policy funds and contract claims	-14,171	-17,288
Change in collateral held for derivatives	-326,248	-98,351
Change in other liabilities	-7,113	-30,056
Other	-1,307	-1,708
Net cash provided by (used in) operating activities	-140,215	48,163
Sales, maturities, or repayments of investments:
Fixed maturity securities - available for sale	276,734	208,747
Mortgage loans on real estate	109,846	84,735
Derivative instruments	214,667	241,098
Other investments	7,218	8,942
Acquisition of investments:
Fixed maturity securities - available for sale	-1,434,934	-974,244
Mortgage loans on real estate	-104,793	-90,056
Derivative instruments	-124,948	-103,330
Other investments	-3,385	-2,259
Purchases of property, furniture and equipment	-295	-200
Net cash used in investing activities	-1,059,890	-626,567
Financing activities
Receipts credited to annuity and single premium universal life policyholder account balances	1,307,792	915,631
Coinsurance deposits	-33,061	-2,609
Return of annuity policyholder account balances	-492,242	-475,280
Financing fees incurred and deferred	0	-100
Repayment of notes payable	0	-54,583
Proceeds from amounts due under repurchase agreements	15,075	0
Excess tax benefits realized from share-based compensation plans	2,828	3,087
Proceeds from issuance of common stock	4,089	6,093
Change in checks in excess of cash balance	-12,126	-32,192
Net cash provided by financing activities	792,355	360,047
Decrease in cash and cash equivalents	-407,750	-218,357
Cash and cash equivalents at beginning of period	701,514	897,529
Cash and cash equivalents at end of period	293,764	679,172
Cash paid during period for interest:
Interest expense	16,580	17,993
Cash paid during period for income taxes:
Income taxes	114	21,500
Non-cash operating activity:
Deferral of sales inducements	93,591	72,687
Non-cash investing and financing activities:
Real estate acquired in satisfaction of mortgage loans	0	1,713
Common stock issued in extinguishment of debt	$0	$23,177

Significant_Accounting_Policie

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2015
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 month period ended March 31, 2015 are not necessarily indicative of the results that may be expected for the year ended December 31, 2015. 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, 2014.
	Adopted Accounting Pronouncements
	There were no accounting pronouncements that were adopted during the current period.
	New Accounting Pronouncements
	In April 2015, the Financial Accounting Standards Board ("FASB") issued an accounting standards update ("ASU") which requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. This ASU will be effective for us on January 1, 2016, and retroactive application is required. It is not expected to have a material impact on our consolidated financial statements.
	In June 2014, the FASB issued an ASU that requires that a performance target in a share-based payment arrangement that affects vesting and that could be achieved after the requisite service period be treated as a performance condition. The requisite service period ends when the employee can cease rendering service and still be eligible to vest in the award if the performance target is achieved. This ASU will be effective for us on January 1, 2016, and early adoption is permitted, but it is not expected to have a material impact on our consolidated financial statements.

Fair_Values_of_Financial_Instr

Fair Values of Financial Instruments	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Values of Financial Instruments	Fair Values of Financial Instruments
	The following sets forth a comparison of the carrying amounts and fair values of our financial instruments:
		March 31, 2015						December 31, 2014
		Carrying			Fair Value			Carrying		Fair Value
		Amount						Amount
		(Dollars in thousands)
	Assets
	Fixed maturity securities:
	Available for sale	$	34,203,641		$	34,203,641		$	32,445,202	$	32,445,202
	Held for investment	76,479			82,984			76,432		75,838
	Equity securities, available for sale	7,849			7,849			7,805		7,805
	Mortgage loans on real estate	2,433,757			2,484,775			2,434,580		2,493,901
	Derivative instruments	610,764			610,764			731,113		731,113
	Other investments	270,566			277,786			266,488		273,004
	Cash and cash equivalents	293,764			293,764			701,514		701,514
	Coinsurance deposits	3,101,783			2,755,386			3,044,342		2,698,552
	Interest rate caps	2,092			2,092			2,778		2,778
	2015 notes hedges	30,858			30,858			30,291		30,291
	Counterparty collateral	331,035			331,035			206,096		206,096
	Liabilities
	Policy benefit reserves	40,699,395			34,108,047			39,463,987		33,078,978
	Single premium immediate annuity (SPIA) benefit reserves	353,420			365,835			365,440		377,654
	Notes payable	421,919			452,950			421,679		503,349
	Subordinated debentures	246,293			255,160			246,243		244,437
	Amounts due under repurchase agreements	15,075			15,075			—		—
	2015 notes embedded conversion derivative	30,858			30,858			30,291		30,291
	Interest rate swap	3,940			3,940			2,644		2,644
	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 March 31, 2015 and December 31, 2014 are presented below based on the fair value hierarchy levels:
		Total			Quoted			Significant		Significant
		Fair Value			Prices in			Other		Unobservable
					Active			Observable		Inputs
					Markets			Inputs		(Level 3)
					(Level 1)			(Level 2)
		(Dollars in thousands)
	March 31, 2015
	Assets
	Fixed maturity securities:
	Available for sale:
	United States Government full faith and credit	$	38,527		$	4,300		$	34,227	$	—
	United States Government sponsored agencies	1,421,364			—			1,421,364		—
	United States municipalities, states and territories	3,809,862			—			3,809,862		—
	Foreign government obligations	227,541			—			227,541		—
	Corporate securities	22,751,894			12			22,751,882		—
	Residential mortgage backed securities	1,729,315			—			1,728,973		342
	Commercial mortgage backed securities	3,165,829			—			3,165,829		—
	Other asset backed securities	1,059,309			—			1,059,309		—
	Equity securities, available for sale: finance, insurance and real estate	7,849			—			7,849		—
	Derivative instruments	610,764			—			610,764		—
	Cash and cash equivalents	293,764			293,764			—		—
	Interest rate caps	2,092			—			2,092		—
	2015 notes hedges	30,858			—			30,858		—
	Counterparty collateral	331,035			—			331,035		—
		$	35,480,003		$	298,076		$	35,181,585	$	342
	Liabilities
	2015 notes embedded conversion derivative	$	30,858		$	—		$	30,858	$	—
	Interest rate swap	3,940			—			3,940		—
	Fixed index annuities - embedded derivatives	5,865,171			—			—		5,865,171
		$	5,899,969		$	—		$	34,798	$	5,865,171
December 31, 2014
Assets
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	138,460		$	4,255		$	134,205	$	—
United States Government sponsored agencies	1,393,890			—			1,393,890		—
United States municipalities, states and territories	3,723,309			—			3,723,309		—
Foreign government obligations	193,803			—			193,803		—
Corporate securities	21,490,292			11			21,490,281		—
Residential mortgage backed securities	1,751,345			—			1,750,970		375
Commercial mortgage backed securities	2,807,620			—			2,807,620		—
Other asset backed securities	946,483			—			946,483		—
Equity securities, available for sale: finance, insurance and real estate	7,805			—			7,805		—
Derivative instruments	731,113			—			731,113		—
Cash and cash equivalents	701,514			701,514			—		—
Interest rate caps	2,778			—			2,778		—
2015 notes hedges	30,291			—			30,291		—
Counterparty collateral	206,096			—			206,096		—
	$	34,124,799		$	705,780		$	33,418,644	$	375
Liabilities
2015 notes embedded conversion derivative	$	30,291		$	—		$	30,291	$	—
Interest rate swap	2,644			—			2,644		—
Fixed index annuities - embedded derivatives	5,574,653			—			—		5,574,653
	$	5,607,588		$	—		$	32,935	$	5,574,653
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 further 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 March 31, 2015 and December 31, 2014.
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 and appraised property values); 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
None of the financial instruments included in other investments are measured at fair value on a recurring basis. Financial instruments included in other investments 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.
2015 notes hedges
The fair value of these call options has been determined by a third party who applies market observable data such as our common stock price, its dividend yield and its volatility, as well as the time to expiration of the call options to determine a fair value of the buy side of these options.
Counterparty collateral
Amounts reported in other assets of 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 purchased 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 payable
The fair values of our senior unsecured notes and convertible senior 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. Notes 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.
2015 notes embedded conversion derivative
The fair value of this embedded derivative is determined by pricing the call options that hedge this potential liability. The terms of the conversion option are identical to the 2015 notes hedges and the method of determining fair value of the call options is based upon observable market data.
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.
The following tables provide a reconciliation of the beginning and ending balances for our Level 3 assets and liabilities, which are measured at fair value on a recurring basis using significant unobservable inputs for the three months ended March 31, 2015 and 2014:
	Three Months Ended
	March 31,
	2015			2014
	(Dollars in thousands)
Available for sale securities
Beginning balance	$	375		$	1,376
Principal returned	(12		)	(78		)
Amortization of premium/accretion of discount	(57		)	(27		)
Total gains (losses) (realized/unrealized):
Included in other comprehensive income	36			(191		)
Included in operations	—			—
Ending balance	$	342		$	1,080
The Level 3 assets included in the table above are not material to our financial position, results of operations or cash flows, and it is management's opinion that the sensitivity of the inputs used in determining the fair value of these assets is not material as well.
	Three Months Ended
	March 31,
	2015			2014
	(Dollars in thousands)
Fixed index annuities - embedded derivatives
Beginning balance	$	5,574,653		$	4,406,163
Premiums less benefits	360,395			371,953
Change in fair value, net	(69,877		)	(22,203		)
Ending balance	$	5,865,171		$	4,755,913
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 March 31, 2015, were to increase by 100 basis points, the fair value of the embedded derivatives would decrease by $405.6 million recorded through operations as a decrease in the change in fair value of embedded derivatives and there would be a corresponding decrease of $238.0 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 $454.2 million recorded through operations as an increase in the change in fair value of embedded derivatives and there would be a corresponding increase of $261.0 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.

Investments

Investments	3 Months Ended
	Mar. 31, 2015
Investments [Abstract]
Investments	Investments
	At March 31, 2015 and December 31, 2014, the amortized cost and fair value of fixed maturity securities and equity securities were as follows:
		Amortized				Gross				Gross				Fair Value
		Cost				Unrealized				Unrealized
						Gains				Losses
		(Dollars in thousands)
	31-Mar-15
	Fixed maturity securities:
	Available for sale:
	United States Government full faith and credit	$	37,114			$	1,417			$	(4	)		$	38,527
	United States Government sponsored agencies	1,384,476				45,559				(8,671		)		1,421,364
	United States municipalities, states and territories	3,345,258				464,981				(377		)		3,809,862
	Foreign government obligations	210,918				21,023				(4,400		)		227,541
	Corporate securities	20,864,311				1,973,728				(86,145		)		22,751,894
	Residential mortgage backed securities	1,571,548				159,281				(1,514		)		1,729,315
	Commercial mortgage backed securities	3,017,014				149,269				(454		)		3,165,829
	Other asset backed securities	1,012,680				54,766				(8,137		)		1,059,309
		$	31,443,319			$	2,870,024			$	(109,702	)		$	34,203,641
	Held for investment:
	Corporate security	$	76,479			$	6,505			$	—			$	82,984
	Equity securities, available for sale:
	Finance, insurance, and real estate	$	7,511			$	338			$	—			$	7,849
	December 31, 2014
	Fixed maturity securities:
	Available for sale:
	United States Government full faith and credit	$	137,710			$	765			$	(15	)		$	138,460
	United States Government sponsored agencies	1,364,424				43,399				(13,933		)		1,393,890
	United States municipalities, states and territories	3,293,551				430,469				(711		)		3,723,309
	Foreign government obligations	181,128				16,628				(3,953		)		193,803
	Corporate securities	19,984,747				1,628,941				(123,396		)		21,490,292
	Residential mortgage backed securities	1,616,846				136,704				(2,205		)		1,751,345
	Commercial mortgage backed securities	2,720,294				90,649				(3,323		)		2,807,620
	Other asset backed securities	906,346				48,022				(7,885		)		946,483
		$	30,205,046			$	2,395,577			$	(155,421	)		$	32,445,202
	Held for investment:
	Corporate security	$	76,432			$	—			$	(594	)		$	75,838
	Equity securities, available for sale:
	Finance, insurance, and real estate	$	7,509			$	296			$	—			$	7,805
	At March 31, 2015, 34% of our fixed income securities have call features, of which 0.6% ($0.2 billion) were subject to call redemption and another 4% ($1.2 billion) will become subject to call redemption during the next twelve months. Approximately 60% 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 March 31, 2015, 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				Fair Value				Amortized				Fair Value
		Cost								Cost
		(Dollars in thousands)
	Due in one year or less	$	79,405			$	81,179			$	—			$	—
	Due after one year through five years	1,537,898				1,706,024				—				—
	Due after five years through ten years	8,936,938				9,293,120				—				—
	Due after ten years through twenty years	7,579,323				8,366,229				—				—
	Due after twenty years	7,708,513				8,802,636				76,479				82,984
		25,842,077				28,249,188				76,479				82,984
	Residential mortgage backed securities	1,571,548				1,729,315				—				—
	Commercial mortgage backed securities	3,017,014				3,165,829				—				—
	Other asset backed securities	1,012,680				1,059,309				—				—
		$	31,443,319			$	34,203,641			$	76,479			$	82,984
	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:
		March 31, 2015				31-Dec-14
		(Dollars in thousands)
	Net unrealized gains on available for sale fixed maturity securities and equity securities	$	2,760,660			$	2,240,452
	Adjustments for assumed changes in amortization of deferred policy acquisition costs and deferred sales inducements	(1,420,347		)		(1,165,271		)
	Deferred income tax valuation allowance reversal	22,534				22,534
	Deferred income tax expense	(469,109		)		(376,314		)
	Net unrealized gains reported as accumulated other comprehensive income	$	893,738			$	721,401
	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 98% of our fixed maturity portfolio rated investment grade at both March 31, 2015 and December 31, 2014.
	The following table summarizes the credit quality, as determined by NAIC designation, of our fixed maturity portfolio as of the dates indicated:
		March 31, 2015								December 31, 2014
NAIC		Amortized Cost				Fair Value				Amortized Cost				Fair Value
Designation
		(Dollars in thousands)
1		$	19,969,022			$	22,027,864			$	19,223,151			$	20,941,634
2		10,833,446				11,565,940				10,432,593				10,981,618
3		681,662				671,393				602,191				583,313
4		35,082				21,074				22,888				14,089
5		—				—				—				—
6		586				354				655				386
		$	31,519,798			$	34,286,625			$	30,281,478			$	32,521,040
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 213 and 402 securities, respectively) have been in a continuous unrealized loss position, at March 31, 2015 and December 31, 2014:
	Less than 12 months								12 months or more								Total
	Fair Value				Unrealized				Fair Value				Unrealized				Fair Value				Unrealized
					Losses								Losses								Losses
	(Dollars in thousands)
March 31, 2015
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	508			$	(4	)		$	—			$	—			$	508			$	(4	)
United States Government sponsored agencies	585,574				(8,671		)		—				—				585,574				(8,671		)
United States municipalities, states and territories	50,040				(322		)		2,945				(55		)		52,985				(377		)
Foreign government obligations	9,044				(1,232		)		11,251				(3,168		)		20,295				(4,400		)
Corporate securities:
Finance, insurance and real estate	182,005				(1,464		)		79,738				(10,022		)		261,743				(11,486		)
Manufacturing, construction and mining	703,225				(30,909		)		235,075				(24,455		)		938,300				(55,364		)
Utilities and related sectors	339,510				(10,650		)		64,467				(2,500		)		403,977				(13,150		)
Wholesale/retail trade	71,296				(1,058		)		23,733				(2,727		)		95,029				(3,785		)
Services, media and other	149,762				(1,234		)		37,022				(1,126		)		186,784				(2,360		)
Residential mortgage backed securities	13,147				(149		)		7,292				(1,365		)		20,439				(1,514		)
Commercial mortgage backed securities	110,898				(454		)		—				—				110,898				(454		)
Other asset backed securities	125,651				(1,533		)		25,371				(6,604		)		151,022				(8,137		)
	$	2,340,660			$	(57,680	)		$	486,894			$	(52,022	)		$	2,827,554			$	(109,702	)
December 31, 2014
Fixed maturity securities:
Available for sale:
United States Government full faith and credit	$	—			$	—			$	498			$	(15	)		$	498			$	(15	)
United States Government sponsored agencies	—				—				610,339				(13,933		)		610,339				(13,933		)
United States municipalities, states and territories	—				—				27,947				(711		)		27,947				(711		)
Foreign government obligations	14,194				(1,068		)		11,542				(2,885		)		25,736				(3,953		)
Corporate securities:
Finance, insurance and real estate	253,439				(2,586		)		399,874				(16,277		)		653,313				(18,863		)
Manufacturing, construction and mining	1,078,089				(35,151		)		694,088				(35,926		)		1,772,177				(71,077		)
Utilities and related sectors	373,952				(8,185		)		344,313				(10,153		)		718,265				(18,338		)
Wholesale/retail trade	88,766				(2,290		)		99,427				(3,122		)		188,193				(5,412		)
Services, media and other	131,940				(1,567		)		277,296				(8,139		)		409,236				(9,706		)
Residential mortgage backed securities	22,115				(1,219		)		20,427				(986		)		42,542				(2,205		)
Commercial mortgage backed securities	241,637				(1,344		)		187,241				(1,979		)		428,878				(3,323		)
Other asset backed securities	142,094				(3,519		)		58,958				(4,366		)		201,052				(7,885		)
	$	2,346,226			$	(56,929	)		$	2,731,950			$	(98,492	)		$	5,078,176			$	(155,421	)
Held for investment:
Corporate security:
Insurance	$	—			$	—			$	75,838			$	(594	)		$	75,838			$	(594	)
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 March 31, 2015 are principally related to timing of the purchases of these securities, which carry less yield than those available at March 31, 2015. In addition, a number of securities have seen their credit spreads remain wide due to issuer or industry specific news while some financial and industrial sector credit spreads remain wide due to continued economic uncertainty and concerns of economic instability.
At March 31, 2015, we had no exposure to sub-prime residential mortgage backed securities. All of our residential mortgage backed securities are pools of first-lien residential mortgage loans. Substantially all of the securities that we own are in the most senior tranche of the securitization in which they are structured and are not subordinated to any other tranche. Our "Alt-A" residential mortgage backed securities are comprised of 34 securities with a total amortized cost basis of $235.8 million and a fair value of $264.6 million.
Approximately 64% and 78% of the unrealized losses on fixed maturity securities shown in the above table for March 31, 2015 and December 31, 2014, 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 months ended March 31, 2015 and 2014 are as follows:
	Three Months Ended
	March 31,
	2015				2014
	(Dollars in thousands)
Fixed maturity securities held for investment carried at amortized cost	$	7,099			$	4,037
Investments carried at fair value:
Fixed maturity securities, available for sale	$	520,166			$	977,131
Equity securities, available for sale	42				(13		)
	520,208				977,118
Adjustment for effect on other balance sheet accounts:
Deferred policy acquisition costs and deferred sales inducements	(255,076		)		(536,752		)
Deferred income tax asset/liability	(92,795		)		(154,127		)
	(347,871		)		(690,879		)
Change in net unrealized gains on investments carried at fair value	$	172,337			$	286,239
Proceeds from sales of available for sale securities for the three months ended March 31, 2015 and 2014 were $169.4 million and $56.1 million, respectively. Scheduled principal repayments, calls and tenders for available for sale securities for the three months ended March 31, 2015 and 2014 were $107.3 million and $152.7 million, 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 (losses) on investments, excluding net OTTI losses for the three months ended March 31, 2015 and 2014, are as follows:
	Three Months Ended
	March 31,
	2015				2014
	(Dollars in thousands)
Available for sale fixed maturity securities:
Gross realized gains	$	2,288			$	184
Gross realized losses	(289		)		(691		)
	1,999				(507		)
Other investments:
Gain on sale of real estate	838				756
Loss on sale of real estate	(382		)		—
Impairment losses on real estate	(629		)		(799		)
	(173		)		(43		)
Mortgage loans on real estate:
Decrease (increase) in allowance for credit losses	1,798				(164		)
Recovery of specific allowance	1,255				—
	3,053				(164		)
	$	4,879			$	(714	)
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, risk or duration profiles as they pertain to our asset liability management.
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 three months ended March 31, 2015 and 2014, 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
Three months ended March 31, 2015
Prime		2006		6.5	%		6.5	%		14	%		14	%		40	%		40	%
Three months ended March 31, 2014
Prime		2006		6.5	%		7.4	%		11	%		12	%		50	%		50	%
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 months ended March 31, 2015 and 2014, by asset type:
	Number		Total OTTI				Portion of OTTI				Net OTTI
	of		Losses				Losses				Losses
	Securities						Recognized				Recognized in
							from Other				Operations
							Comprehensive
							Income
			(Dollars in thousands)
Three months ended March 31, 2015
Fixed maturity securities, available for sale:
Residential mortgage backed securities	1		$	(132	)		$	—			$	(132	)
Three months ended March 31, 2014
Fixed maturity securities, available for sale:
Residential mortgage backed securities	2		—				(905		)		(905		)
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
	March 31,
	2015				2014
	(Dollars in thousands)
Cumulative credit loss at beginning of period	$	(127,050	)		$	(125,960	)
Credit losses on securities for which OTTI has not previously been recognized	(132		)		—
Additional credit losses on securities for which OTTI has previously been recognized	—				(905		)
Accumulated losses on securities that were disposed of during the period	—				—
Cumulative credit loss at end of period	$	(127,182	)		$	(126,865	)
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 (loss), by major type of security, for securities that are part of our investment portfolio at March 31, 2015 and December 31, 2014:
	Amortized Cost				OTTI				Change in Fair				Fair Value
					Recognized in				Value Since
					Other				OTTI was
					Comprehensive				Recognized
					Income
	(Dollars in thousands)
March 31, 2015
Fixed maturity securities, available for sale:
Corporate securities	$	—			$	—			$	12			$	12
Residential mortgage backed securities	551,990				(173,494		)		219,811				598,307
	$	551,990			$	(173,494	)		$	219,823			$	598,319
December 31, 2014
Fixed maturity securities, available for sale:
Corporate securities	$	—			$	—			$	11			$	11
Residential mortgage backed securities	569,508				(173,494		)		215,625				611,639
	$	569,508			$	(173,494	)		$	215,636			$	611,650

Mortgage_Loans_on_Real_Estate

Mortgage Loans on Real Estate	3 Months Ended
	Mar. 31, 2015
Mortgage Loans on Real Estate [Abstract]
Mortgage Loans on Real Estate	Mortgage Loans on Real Estate
	Our mortgage loan portfolio, summarized in the following table, totaled $2.4 billion at both March 31, 2015 and December 31, 2014, with commitments outstanding of $87.0 million at March 31, 2015.
		March 31, 2015				December 31, 2014
		(Dollars in thousands)
	Principal outstanding	$	2,453,692			$	2,457,721
	Loan loss allowance	(19,452		)		(22,633		)
	Deferred prepayment fees	(483		)		(508		)
	Carrying value	$	2,433,757			$	2,434,580
	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:
		March 31, 2015							December 31, 2014
		Principal				Percent			Principal				Percent
		(Dollars in thousands)
	Geographic distribution
	East	$	714,054			29.1	%		$	701,638			28.5	%
	Middle Atlantic	164,954				6.7	%		166,249				6.8	%
	Mountain	279,605				11.4	%		279,075				11.4	%
	New England	9,589				0.4	%		12,280				0.5	%
	Pacific	301,176				12.3	%		302,307				12.3	%
	South Atlantic	475,064				19.4	%		471,849				19.2	%
	West North Central	341,682				13.9	%		349,028				14.2	%
	West South Central	167,568				6.8	%		175,295				7.1	%
		$	2,453,692			100	%		$	2,457,721			100	%
	Property type distribution
	Office	$	457,690			18.7	%		$	484,585			19.7	%
	Medical Office	87,104				3.5	%		88,275				3.6	%
	Retail	712,473				29	%		711,775				29	%
	Industrial/Warehouse	664,136				27.1	%		649,425				26.4	%
	Hotel	22,519				0.9	%		30,640				1.3	%
	Apartment	353,693				14.4	%		335,087				13.6	%
	Mixed use/other	156,077				6.4	%		157,934				6.4	%
		$	2,453,692			100	%		$	2,457,721			100	%
	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								Three Months Ended
		31-Mar-15								31-Mar-14
		Specific				General Allowance				Specific				General Allowance
		Allowance								Allowance
		(Dollars in thousands)
	Beginning allowance balance	$	(12,333	)		$	(10,300	)		$	(16,847	)		$	(9,200	)
	Charge-offs	128				—				949				—
	Recoveries	1,255				—				—				—
	Change in provision for credit losses	(1,502		)		3,300				(564		)		400
	Ending allowance balance	$	(12,452	)		$	(7,000	)		$	(16,462	)		$	(8,800	)
	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:
		March 31, 2015				December 31, 2014
		(Dollars in thousands)
	Individually evaluated for impairment	$	30,763			$	29,116
	Collectively evaluated for impairment	2,422,929				2,428,605
	Total loans evaluated for impairment	$	2,453,692			$	2,457,721
	Charge-offs include allowances that have been established on loans that were satisfied by taking ownership of the collateral. When the property is taken it is recorded at the lower of the mortgage loan's carrying value or the property's fair value 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).
	During the three months ended March 31, 2015, no mortgage loans were satisfied by taking ownership of the real estate serving as collateral compared to one mortgage loan for the same period in 2014. The following table summarizes the activity in the real estate owned, included in Other investments, which was obtained in satisfaction of mortgage loans on real estate:
		Three Months Ended
		March 31,
		2015				2014
		(Dollars in thousands)
	Real estate owned at beginning of period	$	20,238			$	22,844
	Real estate acquired in satisfaction of mortgage loans	—				1,713
	Sales	(4,899		)		(3,030		)
	Impairments	(629		)		(799		)
	Depreciation	(99		)		(136		)
	Real estate owned at end of period	$	14,611			$	20,592
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.
	March 31, 2015				December 31, 2014
	(Dollars in thousands)
Credit Exposure--By Payment Activity
Performing	$	2,436,604			$	2,451,760
In workout	9,928				—
Delinquent	2,316				—
Collateral dependent	4,844				5,961
	$	2,453,692			$	2,457,721
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 past due. 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 a non-accrual status at March 31, 2015 and December 31, 2014 totaled $4.8 million and $6.0 million, respectively.
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				Total			Current		Collateral Dependent Receivables		Total Financing Receivables
									and Over				Past Due
	(Dollars in thousands)
Commercial Mortgage Loans
31-Mar-15	$	11,281			$	2,316			$	—			$	13,597		$	2,435,251	$	4,844	$	2,453,692
31-Dec-14	$	—			$	—			$	—			$	—		$	2,451,760	$	5,961	$	2,457,721
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 more than 60 days 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				Unpaid Principal Balance				Related
	Investment								Allowance
	(Dollars in thousands)
March 31, 2015
Mortgage loans with an allowance	$	18,311			$	30,763			$	(12,452	)
Mortgage loans with no related allowance	13,087				13,087				—
	$	31,398			$	43,850			$	(12,452	)
December 31, 2014
Mortgage loans with an allowance	$	16,783			$	29,116			$	(12,333	)
Mortgage loans with no related allowance	2,656				2,656				—
	$	19,439			$	31,772			$	(12,333	)
	Average Recorded Investment				Interest Income Recognized
	(Dollars in thousands)
Three months ended March 31, 2015
Mortgage loans with an allowance	$	19,158			$	451
Mortgage loans with no related allowance	13,107				159
	$	32,265			$	610
Three months ended March 31, 2014
Mortgage loans with an allowance	$	29,884			$	508
Mortgage loans with no related allowance	3,456				351
	$	33,340			$	859
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 March 31, 2015 and December 31, 2014 that we determined to be TDRs are as follows:
Geographic Region		Number		Principal				Specific Loan Loss Allowance				Net
		of TDRs		Balance								Carrying
				Outstanding								Amount
				(Dollars in thousands)
March 31, 2015
South Atlantic		6		$	11,033			$	(2,992	)		$	8,041
East North Central		2		3,363				(467		)		2,896
West North Central		2		7,790				(1,046		)		6,744
		10		$	22,186			$	(4,505	)		$	17,681
December 31, 2014
South Atlantic		7		14,475				(4,244		)		10,231
East North Central		1		2,177				(467		)		1,710
West North Central		1		1,881				(1,047		)		834
		9		$	18,533			$	(5,758	)		$	12,775

Derivative_Instruments

Derivative Instruments	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments
	We recognize all derivative instruments as assets or liabilities in the consolidated balance sheets at fair value. 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 and derivative instruments embedded in a convertible debt issue, presented in the consolidated balance sheets are as follows:
		March 31,				December 31,
		2015				2014
		(Dollars in thousands)
	Assets
	Derivative instruments
	Call options	$	610,764			$	731,113
	Other assets
	2015 notes hedges	30,858				30,291
	Interest rate caps	2,092				2,778
		$	643,714			$	764,182
	Liabilities
	Policy benefit reserves - annuity products
	Fixed index annuities - embedded derivatives	$	5,865,171			$	5,574,653
	Other liabilities
	2015 notes embedded conversion derivative	30,858				30,291
	Interest rate swap	3,940				2,644
		$	5,899,969			$	5,607,588
	The changes in fair value of derivatives included in the unaudited consolidated statements of operations are as follows:
		Three Months Ended
		March 31,
		2015				2014
		(Dollars in thousands)
	Change in fair value of derivatives:
	Call options	$	(29,220	)		$	71,473
	2015 notes hedges	567				(20,401		)
	Interest rate swap	(1,761		)		(1,402		)
	Interest rate caps	(686		)		(1,177		)
		$	(31,100	)		$	48,493
	Change in fair value of embedded derivatives:
	Fixed index annuities—embedded derivatives	$	50,646			$	113,020
	2015 notes embedded conversion derivative	567				(20,401		)
		$	51,213			$	92,619
	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 under these agreements 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:
							March 31, 2015							December 31, 2014
	Counterparty		Credit Rating		Credit Rating (Moody's)		Notional				Fair Value			Notional			Fair Value
			(S&P)				Amount							Amount
							(Dollars in thousands)
	Bank of America		A		A2		$	3,152,382			$	76,489		$	2,114,812		$	62,932
	Barclays		A		A2		4,014,576				122,621			4,083,259			135,609
	BNP Paribas		A+		A1		1,379,283				37,110			1,321,136			42,644
	Citibank, N.A.		A		A2		2,928,152				53,952			3,190,204			96,759
	Credit Suisse		A		A1		1,825,842				40,812			2,354,811			75,381
	Deutsche Bank		A		A3		2,812,033				49,973			2,682,960			64,028
	HSBC		AA-		A1		21,141				922			38,599			1,767
	J.P. Morgan		A+		Aa3		343,720				6,068			401,804			13,488
	Morgan Stanley		A-		Baa2		2,758,628				59,904			2,605,687			77,106
	Royal Bank of Canada		AA-		Aa3		1,496,512				42,056			1,364,362			41,717
	SunTrust		A-		A3		617,049				12,728			248,622			5,405
	Wells Fargo		AA-		Aa3		3,808,266				108,129			3,550,188			114,277
							$	25,157,584			$	610,764		$	23,956,444		$	731,113
	As of March 31, 2015 and December 31, 2014, we held $541.7 million and $743.0 million, 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 $89.1 million and $47.4 million at March 31, 2015 and December 31, 2014, 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, 2014 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				March 31, 2015			December 31, 2014
	Maturity Date		Amount				Receive Rate		Rate			Counterparty	Fair Value			Fair Value
													(Dollars in thousands)
	15-Mar-21		$	85,500			LIBOR		2.415	%		SunTrust	$	(3,940	)	$	(2,644	)
	Details regarding the interest rate caps are as follows:
			Notional						Cap				March 31, 2015			December 31, 2014
Maturity Date		Amount				Floating Rate		Rate			Counterparty	Fair Value			Fair Value
												(Dollars in thousands)
7-Jul-21		$	40,000			LIBOR		2.5	%		SunTrust	$	1,052		$	1,398
8-Jul-21		12,000				LIBOR		2.5	%		SunTrust	316			420
29-Jul-21		27,000				LIBOR		2.5	%		SunTrust	724			960
		$	79,000									$	2,092		$	2,778
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 March 31, 2015, we had collateral of $1.7 million on deposit related to the swap and caps.
In September 2010, concurrently with the issuance of $200.0 million principal amount of 3.50% Convertible Senior Notes due September 15, 2015 (the "2015 notes"), we entered into hedge transactions (the "2015 notes hedges") with two counterparties whereby we would receive the cash equivalent of the conversion spread on 16.0 million shares of our common stock based upon a strike price of $12.50 per share, subject to certain conversion rate adjustments in the 2015 notes. The number of shares and strike price of the 2015 notes hedges are subject to adjustment based on dividends we pay subsequent to their purchase. The 2015 notes hedges expire on September 15, 2015, and must be settled in cash. The 2015 notes hedges are accounted for as derivative assets and are included in other assets in our consolidated balance sheets. The 2015 notes hedges and 2015 notes embedded conversion derivative are adjusted to fair value each reporting period and unrealized gains and losses are reflected in our consolidated statements of operations.
In separate transactions, we sold warrants (the "2015 warrants") to the 2015 notes hedges counterparties for the purchase of up to 16.0 million shares of our common stock at a price of $16.00 per share. We received $15.6 million in cash proceeds from the sale of the 2015 warrants, which was recorded as an increase in additional paid-in capital. The number of shares and strike price of the warrants are subject to adjustment based on dividends we pay subsequent to selling the warrants. The warrants expire on various dates from December 2015 through March 2016 and are intended to be settled in net shares. Changes in the fair value of these warrants will not be recognized in our consolidated financial statements as long as the instruments remain classified as equity.
At March 31, 2015 and December 31, 2014, as a result of partial unwind transactions executed in 2013 and 2014 and cash dividend adjustments, we had 2015 notes hedges and 2015 warrants outstanding on 1.8 million shares of our common stock at strike prices of $12.25 and $15.68 per share, respectively.
At March 31, 2015 and 2014, the remaining 2015 warrants were dilutive as the average price of our common stock exceeded the strike price of the 2015 warrants and the effect has been included in diluted earnings per share for the three months ended March 31, 2015 and 2014.

Notes_Payable

Notes Payable	3 Months Ended
	Mar. 31, 2015
Debt Disclosure [Abstract]
Notes Payable	Notes Payable
	The carrying amount of the 2015 notes and the amount by which the if-converted value exceeds the outstanding principal for the 2015 notes is as follows:
		March 31, 2015			December 31, 2014
		(Dollars in thousands)
	Principal amount of liability component	$	22,377		$	22,377
	Unamortized discount	(458		)	(698		)
	Net carrying amount of liability component	$	21,919		$	21,679
	Amount by which the if-converted value exceeds principal	$	30,389		$	30,497
	The discount is being amortized over the expected life of the 2015 notes, which is the maturity date of September 15, 2015. The effective interest rate for the 2015 notes is 8.9%. The interest cost recognized in operations for the convertible notes, inclusive of the coupon and amortization of the discount and debt issue costs, was $0.5 million and $3.4 million for the three months ended March 31, 2015 and 2014, respectively. The 2015 notes are excluded from the dilutive effect in our diluted earnings per share calculation as they are intended to be settled only in cash.
	We have a $140 million unsecured revolving line of credit agreement with five banks that terminates on November 22, 2017. The interest rate is floating at a rate based on our election that will be equal to the alternate base rate (as defined in the credit agreement) plus the applicable margin or the adjusted LIBOR rate (as defined in the credit agreement) plus the applicable margin. We also pay a commitment fee based on the available unused portion of the credit facility. The applicable margin and commitment fee rate are based on our credit rating and can change throughout the period of the credit facility. Based upon our current credit rating, the applicable margin is 1.00% for alternate base rate borrowings and 2.00% for adjusted LIBOR rate borrowings, and the commitment fee is 0.35%. Under this agreement, we are required to maintain a minimum risk-based capital ratio at our subsidiary, American Equity Investment Life Insurance Company ("American Equity Life"), of 275%, a maximum ratio of adjusted debt to total adjusted capital of 0.35, and a minimum level of statutory surplus at American Equity Life equal to the sum of 1) 80% of statutory surplus at September 30, 2013, 2) 50% of the statutory net income for each fiscal quarter ending after September 30, 2013, and 3) 50% of all capital contributed to American Equity Life after September 30, 2013. The agreement contains an accordion feature that allows us, on up to three occasions and subject to credit availability, to increase the credit facility by an additional $50 million in the aggregate. We also have the ability to extend the maturity date by an additional one year past the initial maturity date of November 22, 2017 with the consent of the extending banks. There are currently no guarantors of the credit facility, but certain of our subsidiaries must guarantee our obligations under the credit agreement if such subsidiaries guarantee other material amounts of our debt. No amounts were outstanding at March 31, 2015 and December 31, 2014. As of March 31, 2015, $534.0 million is unrestricted and could be distributed to shareholders and still be in compliance with all covenants under this credit agreement.
	As part of our investment strategy, we enter into securities repurchase agreements (short-term collateralized borrowings). The maximum amount borrowed was $40.6 million and $138.7 million during the three months ended March 31, 2015 and 2014, respectively. 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 $1.9 million and $27.5 million for the three months ended March 31, 2015 and 2014, respectively. The weighted average interest rate on amounts due under repurchase agreements was 0.39% and 0.15% for the three months ended March 31, 2015 and 2014, respectively.

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2015
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 SEC, FINRA, 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.
	In recent years, companies in the life insurance and annuity business have faced litigation, including class action lawsuits, alleging improper product design, improper sales practices and similar claims. We were a defendant in a purported class action, McCormack, et al. v. American Equity Investment Life Insurance Company, et al., in the United States District Court for the Central District of California, Western Division and Anagnostis v. American Equity, et al., coordinated in the Central District, entitled, In Re: American Equity Annuity Practices and Sales Litigation (complaint filed September 7, 2005) (the "Los Angeles Case"), involving allegations of improper sales practices and similar claims.
	The Los Angeles Case was a consolidated action involving several lawsuits filed by putative class members seeking class action status for a national class of purchasers of annuities issued by us. On July 30, 2013, the parties entered into a settlement agreement and stipulated to certification of the case as a class action for settlement purposes only. Notice of the terms of the settlement was mailed to the members of the class on October 7, 2013 and settlement claim forms were due from members of the class on or before December 6, 2013. On January 27, 2014, a hearing was held regarding the fairness of the settlement. On January 29, 2014, the District Court signed a final order approving the settlement and finding the settlement is fair and represents a complete resolution of all claims asserted on behalf of the class. On January 30, 2014, a final judgment was entered dismissing the case on the merits and with prejudice. On February 28, 2014, a member of the class filed an appeal of the District Court's approval of the terms of the settlement agreement with the United States Court of Appeals for the Ninth Circuit.
	We recorded an estimated litigation liability of $17.5 million during the third quarter of 2012 related to the Los Angeles Case. We increased our estimated litigation liability for this matter to $21.2 million during the fourth quarter of 2013 following the passage of the deadline for submission of claims by class members in the lawsuit and based upon information available at that time. However, we decreased the liability by $2.3 million in the first quarter of 2014 as additional information became available concerning the nature and magnitude of the claims received. In addition, during the first quarter of 2014, we paid $7.8 million in legal fees to the plaintiffs' counsel. The estimated litigation liability at March 31, 2015 is $11.1 million. While review of the claim forms has been stayed due to the appeal and it is difficult to predict the amount of the liabilities that will ultimately result from the completion of the claims process, the $11.1 million litigation liability represents our best estimate of probable loss with respect to this litigation. In light of the inherent uncertainties involved in the matter described above, there can be no assurance that such litigation, or any other 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 March 31, 2015 to limited partnerships of $28.6 million and to secured bank loans of $11.2 million.

Earnings_Loss_Per_Share

Earnings (Loss) Per Share	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	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
		March 31,
		2015			2014
		(Dollars in thousands, except per share data)
	Numerator:
	Net income (loss) - numerator for earnings (loss) per common share	$	5,903		$	(9,753	)
	Denominator:
	Weighted average common shares outstanding (1)	77,041,704			72,518,574
	Effect of dilutive securities:
	Convertible senior notes	—			3,400,986
	2015 warrants	806,485			2,372,404
	Stock options and deferred compensation agreements	1,159,334			1,287,267
	Restricted stock and restricted stock units	110,511			36,548
	Denominator for earnings (loss) per common share - assuming dilution	79,118,034			79,615,779
	Earnings (loss) per common share	$	0.08		$	(0.13	)
	Earnings (loss) per common share - assuming dilution	$	0.07		$	(0.13	)
	-1	Weighted average common shares outstanding include shares vested under the NMO Deferred Compensation Plan and exclude unallocated shares held by the ESOP.
	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 per share because the options' exercise price was greater than the average market price of the common shares are as follows:
	Period		Number of	Range of
			Shares	Exercise Prices
				Minimum		Maximum
	Three months ended March 31, 2015		—	$—		$—
	Three months ended March 31, 2014		1,277,650	$24.79		$24.79

Significant_Accounting_Policie1

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
New Accounting Pronouncements, Policy	Adopted Accounting Pronouncements
	There were no accounting pronouncements that were adopted during the current period.
	New Accounting Pronouncements
	In April 2015, the Financial Accounting Standards Board ("FASB") issued an accounting standards update ("ASU") which requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. This ASU will be effective for us on January 1, 2016, and retroactive application is required. It is not expected to have a material impact on our consolidated financial statements.
	In June 2014, the FASB issued an ASU that requires that a performance target in a share-based payment arrangement that affects vesting and that could be achieved after the requisite service period be treated as a performance condition. The requisite service period ends when the employee can cease rendering service and still be eligible to vest in the award if the performance target is achieved. This ASU will be effective for us on January 1, 2016, and early adoption is permitted, but it is not expected to have a material impact on our consolidated financial statements.
Fair Values of Financial Instruments, Policy	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.
Investments, Policy	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 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.
Mortgage Loans on Real Estate, Allowance for Loan Losses, Policy	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.
Mortgage Loans on Real Estate, Real Estate Acquired Through Foreclosure, Policy	Charge-offs include allowances that have been established on loans that were satisfied by taking ownership of the collateral. When the property is taken it is recorded at the lower of the mortgage loan's carrying value or the property's fair value 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).
Mortgage Loans on Real Estate, Non-Accrual Loan Status, Policy	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 past due. 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.
Mortgage Loans on Real Estate, Troubled Debt Restructuring, Policy	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.
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.

Fair_Values_of_Financial_Instr1

Fair Values of Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2015
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:
		March 31, 2015						December 31, 2014
		Carrying			Fair Value			Carrying		Fair Value
		Amount						Amount
		(Dollars in thousands)
	Assets
	Fixed maturity securities:
	Available for sale	$	34,203,641		$	34,203,641		$	32,445,202	$	32,445,202
	Held for investment	76,479			82,984			76,432		75,838
	Equity securities, available for sale	7,849			7,849			7,805		7,805
	Mortgage loans on real estate	2,433,757			2,484,775			2,434,580		2,493,901
	Derivative instruments	610,764			610,764			731,113		731,113
	Other investments	270,566			277,786			266,488		273,004
	Cash and cash equivalents	293,764			293,764			701,514		701,514
	Coinsurance deposits	3,101,783			2,755,386			3,044,342		2,698,552
	Interest rate caps	2,092			2,092			2,778		2,778
	2015 notes hedges	30,858			30,858			30,291		30,291
	Counterparty collateral	331,035			331,035			206,096		206,096
	Liabilities
	Policy benefit reserves	40,699,395			34,108,047			39,463,987		33,078,978
	Single premium immediate annuity (SPIA) benefit reserves	353,420			365,835			365,440		377,654
	Notes payable	421,919			452,950			421,679		503,349
	Subordinated debentures	246,293			255,160			246,243		244,437
	Amounts due under repurchase agreements	15,075			15,075			—		—
	2015 notes embedded conversion derivative	30,858			30,858			30,291		30,291
	Interest rate swap	3,940			3,940			2,644		2,644
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 March 31, 2015 and December 31, 2014 are presented below based on the fair value hierarchy levels:
		Total			Quoted			Significant		Significant
		Fair Value			Prices in			Other		Unobservable
					Active			Observable		Inputs
					Markets			Inputs		(Level 3)
					(Level 1)			(Level 2)
		(Dollars in thousands)
	March 31, 2015
	Assets
	Fixed maturity securities:
	Available for sale:
	United States Government full faith and credit	$	38,527		$	4,300		$	34,227	$	—
	United States Government sponsored agencies	1,421,364			—			1,421,364		—
	United States municipalities, states and territories	3,809,862			—			3,809,862		—
	Foreign government obligations	227,541			—			227,541		—
	Corporate securities	22,751,894			12			22,751,882		—
	Residential mortgage backed securities	1,729,315			—			1,728,973		342
	Commercial mortgage backed securities	3,165,829			—			3,165,829		—
	Other asset backed securities	1,059,309			—			1,059,309		—
	Equity securities, available for sale: finance, insurance and real estate	7,849			—			7,849		—
	Derivative instruments	610,764			—			610,764		—
	Cash and cash equivalents	293,764			293,764			—		—
	Interest rate caps	2,092			—			2,092		—
	2015 notes hedges	30,858			—			30,858		—
	Counterparty collateral	331,035			—			331,035		—
		$	35,480,003		$	298,076		$	35,181,585	$	342
	Liabilities
	2015 notes embedded conversion derivative	$	30,858		$	—		$	30,858	$	—
	Interest rate swap	3,940			—			3,940		—
	Fixed index annuities - embedded derivatives	5,865,171			—			—		5,865,171
		$	5,899,969		$	—		$	34,798	$	5,865,171
	December 31, 2014
	Assets
	Fixed maturity securities:
	Available for sale:
	United States Government full faith and credit	$	138,460		$	4,255		$	134,205	$	—
	United States Government sponsored agencies	1,393,890			—			1,393,890		—
	United States municipalities, states and territories	3,723,309			—			3,723,309		—
	Foreign government obligations	193,803			—			193,803		—
	Corporate securities	21,490,292			11			21,490,281		—
	Residential mortgage backed securities	1,751,345			—			1,750,970		375
	Commercial mortgage backed securities	2,807,620			—			2,807,620		—
	Other asset backed securities	946,483			—			946,483		—
	Equity securities, available for sale: finance, insurance and real estate	7,805			—			7,805		—
	Derivative instruments	731,113			—			731,113		—
	Cash and cash equivalents	701,514			701,514			—		—
	Interest rate caps	2,778			—			2,778		—
	2015 notes hedges	30,291			—			30,291		—
	Counterparty collateral	206,096			—			206,096		—
		$	34,124,799		$	705,780		$	33,418,644	$	375
	Liabilities
	2015 notes embedded conversion derivative	$	30,291		$	—		$	30,291	$	—
	Interest rate swap	2,644			—			2,644		—
	Fixed index annuities - embedded derivatives	5,574,653			—			—		5,574,653
		$	5,607,588		$	—		$	32,935	$	5,574,653
Assets Measured at Fair Value on Recurring Basis, Level 3 Reconciliation
		Three Months Ended
		March 31,
		2015			2014
		(Dollars in thousands)
	Available for sale securities
	Beginning balance	$	375		$	1,376
	Principal returned	(12		)	(78		)
	Amortization of premium/accretion of discount	(57		)	(27		)
	Total gains (losses) (realized/unrealized):
	Included in other comprehensive income	36			(191		)
	Included in operations	—			—
	Ending balance	$	342		$	1,080
Liabilities Measured at Fair Value on Recurring Basis, Level 3 Reconciliation
		Three Months Ended
		March 31,
		2015			2014
		(Dollars in thousands)
	Fixed index annuities - embedded derivatives
	Beginning balance	$	5,574,653		$	4,406,163
	Premiums less benefits	360,395			371,953
	Change in fair value, net	(69,877		)	(22,203		)
	Ending balance	$	5,865,171		$	4,755,913

Investments_Tables

Investments (Tables)	3 Months Ended
	Mar. 31, 2015
Investments [Abstract]
Schedule of Fixed Maturity and Equity Securities	At March 31, 2015 and December 31, 2014, the amortized cost and fair value of fixed maturity securities and equity securities were as follows:
		Amortized				Gross				Gross				Fair Value
		Cost				Unrealized				Unrealized
						Gains				Losses
		(Dollars in thousands)
	31-Mar-15
	Fixed maturity securities:
	Available for sale:
	United States Government full faith and credit	$	37,114			$	1,417			$	(4	)		$	38,527
	United States Government sponsored agencies	1,384,476				45,559				(8,671		)		1,421,364
	United States municipalities, states and territories	3,345,258				464,981				(377		)		3,809,862
	Foreign government obligations	210,918				21,023				(4,400		)		227,541
	Corporate securities	20,864,311				1,973,728				(86,145		)		22,751,894
	Residential mortgage backed securities	1,571,548				159,281				(1,514		)		1,729,315
	Commercial mortgage backed securities	3,017,014				149,269				(454		)		3,165,829
	Other asset backed securities	1,012,680				54,766				(8,137		)		1,059,309
		$	31,443,319			$	2,870,024			$	(109,702	)		$	34,203,641
	Held for investment:
	Corporate security	$	76,479			$	6,505			$	—			$	82,984
	Equity securities, available for sale:
	Finance, insurance, and real estate	$	7,511			$	338			$	—			$	7,849
	December 31, 2014
	Fixed maturity securities:
	Available for sale:
	United States Government full faith and credit	$	137,710			$	765			$	(15	)		$	138,460
	United States Government sponsored agencies	1,364,424				43,399				(13,933		)		1,393,890
	United States municipalities, states and territories	3,293,551				430,469				(711		)		3,723,309
	Foreign government obligations	181,128				16,628				(3,953		)		193,803
	Corporate securities	19,984,747				1,628,941				(123,396		)		21,490,292
	Residential mortgage backed securities	1,616,846				136,704				(2,205		)		1,751,345
	Commercial mortgage backed securities	2,720,294				90,649				(3,323		)		2,807,620
	Other asset backed securities	906,346				48,022				(7,885		)		946,483
		$	30,205,046			$	2,395,577			$	(155,421	)		$	32,445,202
	Held for investment:
	Corporate security	$	76,432			$	—			$	(594	)		$	75,838
	Equity securities, available for sale:
	Finance, insurance, and real estate	$	7,509			$	296			$	—			$	7,805
Schedule of Fixed Maturity Securities by Contractual Maturity Date	The amortized cost and fair value of fixed maturity securities at March 31, 2015, 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				Fair Value				Amortized				Fair Value
		Cost								Cost
		(Dollars in thousands)
	Due in one year or less	$	79,405			$	81,179			$	—			$	—
	Due after one year through five years	1,537,898				1,706,024				—				—
	Due after five years through ten years	8,936,938				9,293,120				—				—
	Due after ten years through twenty years	7,579,323				8,366,229				—				—
	Due after twenty years	7,708,513				8,802,636				76,479				82,984
		25,842,077				28,249,188				76,479				82,984
	Residential mortgage backed securities	1,571,548				1,729,315				—				—
	Commercial mortgage backed securities	3,017,014				3,165,829				—				—
	Other asset backed securities	1,012,680				1,059,309				—				—
		$	31,443,319			$	34,203,641			$	76,479			$	82,984
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:
		March 31, 2015				31-Dec-14
		(Dollars in thousands)
	Net unrealized gains on available for sale fixed maturity securities and equity securities	$	2,760,660			$	2,240,452
	Adjustments for assumed changes in amortization of deferred policy acquisition costs and deferred sales inducements	(1,420,347		)		(1,165,271		)
	Deferred income tax valuation allowance reversal	22,534				22,534
	Deferred income tax expense	(469,109		)		(376,314		)
	Net unrealized gains reported as accumulated other comprehensive income	$	893,738			$	721,401
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:
			March 31, 2015								December 31, 2014
	NAIC		Amortized Cost				Fair Value				Amortized Cost				Fair Value
	Designation
			(Dollars in thousands)
	1		$	19,969,022			$	22,027,864			$	19,223,151			$	20,941,634
	2		10,833,446				11,565,940				10,432,593				10,981,618
	3		681,662				671,393				602,191				583,313
	4		35,082				21,074				22,888				14,089
	5		—				—				—				—
	6		586				354				655				386
			$	31,519,798			$	34,286,625			$	30,281,478			$	32,521,040
Schedule of Gross Unrealized Losses on Investments, By Category and Length of Time	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 213 and 402 securities, respectively) have been in a continuous unrealized loss position, at March 31, 2015 and December 31, 2014:
		Less than 12 months								12 months or more								Total
		Fair Value				Unrealized				Fair Value				Unrealized				Fair Value				Unrealized
						Losses								Losses								Losses
		(Dollars in thousands)
	March 31, 2015
	Fixed maturity securities:
	Available for sale:
	United States Government full faith and credit	$	508			$	(4	)		$	—			$	—			$	508			$	(4	)
	United States Government sponsored agencies	585,574				(8,671		)		—				—				585,574				(8,671		)
	United States municipalities, states and territories	50,040				(322		)		2,945				(55		)		52,985				(377		)
	Foreign government obligations	9,044				(1,232		)		11,251				(3,168		)		20,295				(4,400		)
	Corporate securities:
	Finance, insurance and real estate	182,005				(1,464		)		79,738				(10,022		)		261,743				(11,486		)
	Manufacturing, construction and mining	703,225				(30,909		)		235,075				(24,455		)		938,300				(55,364		)
	Utilities and related sectors	339,510				(10,650		)		64,467				(2,500		)		403,977				(13,150		)
	Wholesale/retail trade	71,296				(1,058		)		23,733				(2,727		)		95,029				(3,785		)
	Services, media and other	149,762				(1,234		)		37,022				(1,126		)		186,784				(2,360		)
	Residential mortgage backed securities	13,147				(149		)		7,292				(1,365		)		20,439				(1,514		)
	Commercial mortgage backed securities	110,898				(454		)		—				—				110,898				(454		)
	Other asset backed securities	125,651				(1,533		)		25,371				(6,604		)		151,022				(8,137		)
		$	2,340,660			$	(57,680	)		$	486,894			$	(52,022	)		$	2,827,554			$	(109,702	)
	December 31, 2014
	Fixed maturity securities:
	Available for sale:
	United States Government full faith and credit	$	—			$	—			$	498			$	(15	)		$	498			$	(15	)
	United States Government sponsored agencies	—				—				610,339				(13,933		)		610,339				(13,933		)
	United States municipalities, states and territories	—				—				27,947				(711		)		27,947				(711		)
	Foreign government obligations	14,194				(1,068		)		11,542				(2,885		)		25,736				(3,953		)
	Corporate securities:
	Finance, insurance and real estate	253,439				(2,586		)		399,874				(16,277		)		653,313				(18,863		)
	Manufacturing, construction and mining	1,078,089				(35,151		)		694,088				(35,926		)		1,772,177				(71,077		)
	Utilities and related sectors	373,952				(8,185		)		344,313				(10,153		)		718,265				(18,338		)
	Wholesale/retail trade	88,766				(2,290		)		99,427				(3,122		)		188,193				(5,412		)
	Services, media and other	131,940				(1,567		)		277,296				(8,139		)		409,236				(9,706		)
	Residential mortgage backed securities	22,115				(1,219		)		20,427				(986		)		42,542				(2,205		)
	Commercial mortgage backed securities	241,637				(1,344		)		187,241				(1,979		)		428,878				(3,323		)
	Other asset backed securities	142,094				(3,519		)		58,958				(4,366		)		201,052				(7,885		)
		$	2,346,226			$	(56,929	)		$	2,731,950			$	(98,492	)		$	5,078,176			$	(155,421	)
	Held for investment:
	Corporate security:
	Insurance	$	—			$	—			$	75,838			$	(594	)		$	75,838			$	(594	)
Schedule of Changes in Net Unrealized Gains/Losses on Investments	Changes in net unrealized gains on investments for the three months ended March 31, 2015 and 2014 are as follows:
		Three Months Ended
		March 31,
		2015				2014
		(Dollars in thousands)
	Fixed maturity securities held for investment carried at amortized cost	$	7,099			$	4,037
	Investments carried at fair value:
	Fixed maturity securities, available for sale	$	520,166			$	977,131
	Equity securities, available for sale	42				(13		)
		520,208				977,118
	Adjustment for effect on other balance sheet accounts:
	Deferred policy acquisition costs and deferred sales inducements	(255,076		)		(536,752		)
	Deferred income tax asset/liability	(92,795		)		(154,127		)
		(347,871		)		(690,879		)
	Change in net unrealized gains on investments carried at fair value	$	172,337			$	286,239
Net Realized Gains (Losses) on Investments	Net realized gains (losses) on investments, excluding net OTTI losses for the three months ended March 31, 2015 and 2014, are as follows:
		Three Months Ended
		March 31,
		2015				2014
		(Dollars in thousands)
	Available for sale fixed maturity securities:
	Gross realized gains	$	2,288			$	184
	Gross realized losses	(289		)		(691		)
		1,999				(507		)
	Other investments:
	Gain on sale of real estate	838				756
	Loss on sale of real estate	(382		)		—
	Impairment losses on real estate	(629		)		(799		)
		(173		)		(43		)
	Mortgage loans on real estate:
	Decrease (increase) in allowance for credit losses	1,798				(164		)
	Recovery of specific allowance	1,255				—
		3,053				(164		)
		$	4,879			$	(714	)
Significant Assumptions Used to Determine the Credit Loss Component of Other Than Temporary Impairment on Residential Mortgage Backed Securities	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 three months ended March 31, 2015 and 2014, 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
	Three months ended March 31, 2015
	Prime		2006		6.5	%		6.5	%		14	%		14	%		40	%		40	%
	Three months ended March 31, 2014
	Prime		2006		6.5	%		7.4	%		11	%		12	%		50	%		50	%
Other Than Temporary Impairment by Asset Type	The following table summarizes other than temporary impairments for the three months ended March 31, 2015 and 2014, by asset type:
		Number		Total OTTI				Portion of OTTI				Net OTTI
		of		Losses				Losses				Losses
		Securities						Recognized				Recognized in
								from Other				Operations
								Comprehensive
								Income
				(Dollars in thousands)
	Three months ended March 31, 2015
	Fixed maturity securities, available for sale:
	Residential mortgage backed securities	1		$	(132	)		$	—			$	(132	)
	Three months ended March 31, 2014
	Fixed maturity securities, available for sale:
	Residential mortgage backed securities	2		—				(905		)		(905		)
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
		March 31,
		2015				2014
		(Dollars in thousands)
	Cumulative credit loss at beginning of period	$	(127,050	)		$	(125,960	)
	Credit losses on securities for which OTTI has not previously been recognized	(132		)		—
	Additional credit losses on securities for which OTTI has previously been recognized	—				(905		)
	Accumulated losses on securities that were disposed of during the period	—				—
	Cumulative credit loss at end of period	$	(127,182	)		$	(126,865	)
Schedule of Other Than Temporary Impairment Losses, Investments	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 (loss), by major type of security, for securities that are part of our investment portfolio at March 31, 2015 and December 31, 2014:
		Amortized Cost				OTTI				Change in Fair				Fair Value
						Recognized in				Value Since
						Other				OTTI was
						Comprehensive				Recognized
						Income
		(Dollars in thousands)
	March 31, 2015
	Fixed maturity securities, available for sale:
	Corporate securities	$	—			$	—			$	12			$	12
	Residential mortgage backed securities	551,990				(173,494		)		219,811				598,307
		$	551,990			$	(173,494	)		$	219,823			$	598,319
	December 31, 2014
	Fixed maturity securities, available for sale:
	Corporate securities	$	—			$	—			$	11			$	11
	Residential mortgage backed securities	569,508				(173,494		)		215,625				611,639
		$	569,508			$	(173,494	)		$	215,636			$	611,650

Mortgage_Loans_on_Real_Estate_

Mortgage Loans on Real Estate (Tables)	3 Months Ended
	Mar. 31, 2015
Mortgage Loans on Real Estate [Abstract]
Summary of Mortgage Loan Portfolio	Our mortgage loan portfolio, summarized in the following table, totaled $2.4 billion at both March 31, 2015 and December 31, 2014, with commitments outstanding of $87.0 million at March 31, 2015.
		March 31, 2015				December 31, 2014
		(Dollars in thousands)
	Principal outstanding	$	2,453,692			$	2,457,721
	Loan loss allowance	(19,452		)		(22,633		)
	Deferred prepayment fees	(483		)		(508		)
	Carrying value	$	2,433,757			$	2,434,580
Mortgage Loan Portfolio Summarized by Geographic Region and Property Type	The mortgage loan portfolio is summarized by geographic region and property type as follows:
		March 31, 2015							December 31, 2014
		Principal				Percent			Principal				Percent
		(Dollars in thousands)
	Geographic distribution
	East	$	714,054			29.1	%		$	701,638			28.5	%
	Middle Atlantic	164,954				6.7	%		166,249				6.8	%
	Mountain	279,605				11.4	%		279,075				11.4	%
	New England	9,589				0.4	%		12,280				0.5	%
	Pacific	301,176				12.3	%		302,307				12.3	%
	South Atlantic	475,064				19.4	%		471,849				19.2	%
	West North Central	341,682				13.9	%		349,028				14.2	%
	West South Central	167,568				6.8	%		175,295				7.1	%
		$	2,453,692			100	%		$	2,457,721			100	%
	Property type distribution
	Office	$	457,690			18.7	%		$	484,585			19.7	%
	Medical Office	87,104				3.5	%		88,275				3.6	%
	Retail	712,473				29	%		711,775				29	%
	Industrial/Warehouse	664,136				27.1	%		649,425				26.4	%
	Hotel	22,519				0.9	%		30,640				1.3	%
	Apartment	353,693				14.4	%		335,087				13.6	%
	Mixed use/other	156,077				6.4	%		157,934				6.4	%
		$	2,453,692			100	%		$	2,457,721			100	%
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								Three Months Ended
		31-Mar-15								31-Mar-14
		Specific				General Allowance				Specific				General Allowance
		Allowance								Allowance
		(Dollars in thousands)
	Beginning allowance balance	$	(12,333	)		$	(10,300	)		$	(16,847	)		$	(9,200	)
	Charge-offs	128				—				949				—
	Recoveries	1,255				—				—				—
	Change in provision for credit losses	(1,502		)		3,300				(564		)		400
	Ending allowance balance	$	(12,452	)		$	(7,000	)		$	(16,462	)		$	(8,800	)
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:
		March 31, 2015				December 31, 2014
		(Dollars in thousands)
	Individually evaluated for impairment	$	30,763			$	29,116
	Collectively evaluated for impairment	2,422,929				2,428,605
	Total loans evaluated for impairment	$	2,453,692			$	2,457,721
Real Estate Acquired Via Foreclosure or Deed In Lieu	The following table summarizes the activity in the real estate owned, included in Other investments, which was obtained in satisfaction of mortgage loans on real estate:
		Three Months Ended
		March 31,
		2015				2014
		(Dollars in thousands)
	Real estate owned at beginning of period	$	20,238			$	22,844
	Real estate acquired in satisfaction of mortgage loans	—				1,713
	Sales	(4,899		)		(3,030		)
	Impairments	(629		)		(799		)
	Depreciation	(99		)		(136		)
	Real estate owned at end of period	$	14,611			$	20,592
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.
		March 31, 2015				December 31, 2014
		(Dollars in thousands)
	Credit Exposure--By Payment Activity
	Performing	$	2,436,604			$	2,451,760
	In workout	9,928				—
	Delinquent	2,316				—
	Collateral dependent	4,844				5,961
		$	2,453,692			$	2,457,721
Aging of Financing Receivables	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				Total			Current		Collateral Dependent Receivables		Total Financing Receivables
										and Over				Past Due
		(Dollars in thousands)
	Commercial Mortgage Loans
	31-Mar-15	$	11,281			$	2,316			$	—			$	13,597		$	2,435,251	$	4,844	$	2,453,692
	31-Dec-14	$	—			$	—			$	—			$	—		$	2,451,760	$	5,961	$	2,457,721
Impaired Financing Receivables	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 more than 60 days 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				Unpaid Principal Balance				Related
		Investment								Allowance
		(Dollars in thousands)
	March 31, 2015
	Mortgage loans with an allowance	$	18,311			$	30,763			$	(12,452	)
	Mortgage loans with no related allowance	13,087				13,087				—
		$	31,398			$	43,850			$	(12,452	)
	December 31, 2014
	Mortgage loans with an allowance	$	16,783			$	29,116			$	(12,333	)
	Mortgage loans with no related allowance	2,656				2,656				—
		$	19,439			$	31,772			$	(12,333	)
		Average Recorded Investment				Interest Income Recognized
		(Dollars in thousands)
	Three months ended March 31, 2015
	Mortgage loans with an allowance	$	19,158			$	451
	Mortgage loans with no related allowance	13,107				159
		$	32,265			$	610
	Three months ended March 31, 2014
	Mortgage loans with an allowance	$	29,884			$	508
	Mortgage loans with no related allowance	3,456				351
		$	33,340			$	859
Troubled Debt Restructurings on Financing Receivables	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 March 31, 2015 and December 31, 2014 that we determined to be TDRs are as follows:
	Geographic Region		Number		Principal				Specific Loan Loss Allowance				Net
			of TDRs		Balance								Carrying
					Outstanding								Amount
					(Dollars in thousands)
	March 31, 2015
	South Atlantic		6		$	11,033			$	(2,992	)		$	8,041
	East North Central		2		3,363				(467		)		2,896
	West North Central		2		7,790				(1,046		)		6,744
			10		$	22,186			$	(4,505	)		$	17,681
	December 31, 2014
	South Atlantic		7		14,475				(4,244		)		10,231
	East North Central		1		2,177				(467		)		1,710
	West North Central		1		1,881				(1,047		)		834
			9		$	18,533			$	(5,758	)		$	12,775

Derivative_Instruments_Tables

Derivative Instruments (Tables)	3 Months Ended
	Mar. 31, 2015
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 and derivative instruments embedded in a convertible debt issue, presented in the consolidated balance sheets are as follows:
		March 31,				December 31,
		2015				2014
		(Dollars in thousands)
	Assets
	Derivative instruments
	Call options	$	610,764			$	731,113
	Other assets
	2015 notes hedges	30,858				30,291
	Interest rate caps	2,092				2,778
		$	643,714			$	764,182
	Liabilities
	Policy benefit reserves - annuity products
	Fixed index annuities - embedded derivatives	$	5,865,171			$	5,574,653
	Other liabilities
	2015 notes embedded conversion derivative	30,858				30,291
	Interest rate swap	3,940				2,644
		$	5,899,969			$	5,607,588
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
		March 31,
		2015				2014
		(Dollars in thousands)
	Change in fair value of derivatives:
	Call options	$	(29,220	)		$	71,473
	2015 notes hedges	567				(20,401		)
	Interest rate swap	(1,761		)		(1,402		)
	Interest rate caps	(686		)		(1,177		)
		$	(31,100	)		$	48,493
	Change in fair value of embedded derivatives:
	Fixed index annuities—embedded derivatives	$	50,646			$	113,020
	2015 notes embedded conversion derivative	567				(20,401		)
		$	51,213			$	92,619
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:
							March 31, 2015							December 31, 2014
	Counterparty		Credit Rating		Credit Rating (Moody's)		Notional				Fair Value			Notional			Fair Value
			(S&P)				Amount							Amount
							(Dollars in thousands)
	Bank of America		A		A2		$	3,152,382			$	76,489		$	2,114,812		$	62,932
	Barclays		A		A2		4,014,576				122,621			4,083,259			135,609
	BNP Paribas		A+		A1		1,379,283				37,110			1,321,136			42,644
	Citibank, N.A.		A		A2		2,928,152				53,952			3,190,204			96,759
	Credit Suisse		A		A1		1,825,842				40,812			2,354,811			75,381
	Deutsche Bank		A		A3		2,812,033				49,973			2,682,960			64,028
	HSBC		AA-		A1		21,141				922			38,599			1,767
	J.P. Morgan		A+		Aa3		343,720				6,068			401,804			13,488
	Morgan Stanley		A-		Baa2		2,758,628				59,904			2,605,687			77,106
	Royal Bank of Canada		AA-		Aa3		1,496,512				42,056			1,364,362			41,717
	SunTrust		A-		A3		617,049				12,728			248,622			5,405
	Wells Fargo		AA-		Aa3		3,808,266				108,129			3,550,188			114,277
							$	25,157,584			$	610,764		$	23,956,444		$	731,113
Schedule of Interest Rate Derivatives	Details regarding the interest rate swap are as follows:
			Notional						Pay				March 31, 2015			December 31, 2014
	Maturity Date		Amount				Receive Rate		Rate			Counterparty	Fair Value			Fair Value
													(Dollars in thousands)
	15-Mar-21		$	85,500			LIBOR		2.415	%		SunTrust	$	(3,940	)	$	(2,644	)
	Details regarding the interest rate caps are as follows:
			Notional						Cap				March 31, 2015			December 31, 2014
	Maturity Date		Amount				Floating Rate		Rate			Counterparty	Fair Value			Fair Value
													(Dollars in thousands)
	7-Jul-21		$	40,000			LIBOR		2.5	%		SunTrust	$	1,052		$	1,398
	8-Jul-21		12,000				LIBOR		2.5	%		SunTrust	316			420
	29-Jul-21		27,000				LIBOR		2.5	%		SunTrust	724			960
			$	79,000									$	2,092		$	2,778

Notes_Payable_Tables

Notes Payable (Tables)	3 Months Ended
	Mar. 31, 2015
Debt Disclosure [Abstract]
Liability and Equity Components of Convertible Senior Notes	The carrying amount of the 2015 notes and the amount by which the if-converted value exceeds the outstanding principal for the 2015 notes is as follows:
		March 31, 2015			December 31, 2014
		(Dollars in thousands)
	Principal amount of liability component	$	22,377		$	22,377
	Unamortized discount	(458		)	(698		)
	Net carrying amount of liability component	$	21,919		$	21,679
	Amount by which the if-converted value exceeds principal	$	30,389		$	30,497

Earnings_Loss_Per_Share_Tables

Earnings (Loss) Per Share (Tables)	3 Months Ended
	Mar. 31, 2015
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
		March 31,
		2015			2014
		(Dollars in thousands, except per share data)
	Numerator:
	Net income (loss) - numerator for earnings (loss) per common share	$	5,903		$	(9,753	)
	Denominator:
	Weighted average common shares outstanding (1)	77,041,704			72,518,574
	Effect of dilutive securities:
	Convertible senior notes	—			3,400,986
	2015 warrants	806,485			2,372,404
	Stock options and deferred compensation agreements	1,159,334			1,287,267
	Restricted stock and restricted stock units	110,511			36,548
	Denominator for earnings (loss) per common share - assuming dilution	79,118,034			79,615,779
	Earnings (loss) per common share	$	0.08		$	(0.13	)
	Earnings (loss) per common share - assuming dilution	$	0.07		$	(0.13	)
	-1	Weighted average common shares outstanding include shares vested under the NMO Deferred Compensation Plan and exclude unallocated shares held by the ESOP.
Schedule of Antidilutive Securities Excluded from Computation of Earnings (Loss) Per Share	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 per share because the options' exercise price was greater than the average market price of the common shares are as follows:
	Period		Number of	Range of
			Shares	Exercise Prices
				Minimum		Maximum
	Three months ended March 31, 2015		—	$—		$—
	Three months ended March 31, 2014		1,277,650	$24.79		$24.79

Fair_Values_of_Financial_Instr2

Fair Values of Financial Instruments (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Level 1 to Level 2 transfers, amount	$0		$0
Liabilities, Level 1 to Level 2 transfers, amount	0		0
Assets, Level 2 to Level 1 transfers, amount	0		0
Liabilities, Level 2 to Level 1 transfers, amount	0		0
Assets, transfers into Level 3, amount	0	0
Liabilities, transfers into Level 3, amount	0	0
Assets, transfers out of Level 3, amount	0	0
Liabilities, transfers out of Level 3, amount	0	0
Other investments	285,177,000		286,726,000
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	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)	100
Fixed index annuities embedded derivative, adjustment due to change in discount rate	-405,600,000
Deferred policy scquisition costs and deferred sales inducements, combined balance, adjustment due to change in discount rate	-238,000,000
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)	100
Fixed index annuities embedded derivative, adjustment due to change in discount rate	454,200,000
Deferred policy scquisition costs and deferred sales inducements, combined balance, adjustment due to change in discount rate	$261,000,000

Fair_Values_of_Financial_Instr3

Fair Values of Financial Instruments (Fair Values and Carrying Amounts of Financial Instruments) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets
Held for investment	$82,984	$75,838
Other investments	285,177	286,726
Coinsurance deposits	3,101,783	3,044,342
Liabilities
Policy benefit reserves	41,037,401	39,802,861
Carrying Amount [Member]
Assets
Mortgage loans on real estate	2,433,757	2,434,580
Derivative instruments	610,764	731,113
Other investments	270,566	266,488
Cash and cash equivalents	293,764	701,514
Coinsurance deposits	3,101,783	3,044,342
2015 notes hedges	30,858	30,291
Counterparty collateral	331,035	206,096
Liabilities
Policy benefit reserves	40,699,395	39,463,987
Single premium immediate annuity (SPIA) benefit reserves	353,420	365,440
Notes payable	421,919	421,679
Subordinated debentures	246,293	246,243
Amounts due under repurchase agreements	15,075	0
2015 notes embedded conversion derivative	30,858	30,291
Carrying Amount [Member] | Interest Rate Caps [Member]
Assets
Interest rate derivative assets	2,092	2,778
Carrying Amount [Member] | Interest Rate Swap [Member]
Liabilities
Interest rate derivative liabilities	3,940	2,644
Carrying Amount [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	34,203,641	32,445,202
Held for investment	76,479	76,432
Carrying Amount [Member] | Equity Securities [Member]
Assets
Available for sale securities	7,849	7,805
Fair Value [Member]
Assets
Mortgage loans on real estate	2,484,775	2,493,901
Derivative instruments	610,764	731,113
Other investments	277,786	273,004
Cash and cash equivalents	293,764	701,514
Coinsurance deposits	2,755,386	2,698,552
2015 notes hedges	30,858	30,291
Counterparty collateral	331,035	206,096
Liabilities
Policy benefit reserves	34,108,047	33,078,978
Single premium immediate annuity (SPIA) benefit reserves	365,835	377,654
Notes payable	452,950	503,349
Subordinated debentures	255,160	244,437
Amounts due under repurchase agreements	15,075	0
2015 notes embedded conversion derivative	30,858	30,291
Fair Value [Member] | Interest Rate Caps [Member]
Assets
Interest rate derivative assets	2,092	2,778
Fair Value [Member] | Interest Rate Swap [Member]
Liabilities
Interest rate derivative liabilities	3,940	2,644
Fair Value [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	34,203,641	32,445,202
Held for investment	82,984	75,838
Fair Value [Member] | Equity Securities [Member]
Assets
Available for sale securities	$7,849	$7,805

Fair_Values_of_Financial_Instr4

Fair Values of Financial Instruments (Assets and Liabilities Measured on a Recurring Basis by Fair Value Hierarchy) (Details) (Fair Value, Measurements, Recurring [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets
Derivative assets	$610,764	$731,113
Cash and cash equivalents	293,764	701,514
2015 notes hedges	30,858	30,291
Counterparty collateral	331,035	206,096
Assets	35,480,003	34,124,799
Liabilities
2015 notes embedded conversion derivative	30,858	30,291
Fixed index annuities - embedded derivatives	5,865,171	5,574,653
Liabilities	5,899,969	5,607,588
Interest Rate Caps [Member]
Assets
Interest rate derivative assets	2,092	2,778
Interest Rate Swap [Member]
Liabilities
Interest rate derivative liabilities	3,940	2,644
Equity Securities [Member]
Assets
Available for sale securities	7,849	7,805
United States Government Full Faith and Credit [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	38,527	138,460
United States Government Sponsored Agencies [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	1,421,364	1,393,890
United States Municipalities, States and Territories [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	3,809,862	3,723,309
Foreign Government Obligations [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	227,541	193,803
Corporate Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	22,751,894	21,490,292
Residential Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	1,729,315	1,751,345
Commercial Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	3,165,829	2,807,620
Other Asset Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	1,059,309	946,483
Quoted Prices in Active Markets (Level 1) [Member]
Assets
Derivative assets	0	0
Cash and cash equivalents	293,764	701,514
2015 notes hedges	0	0
Counterparty collateral	0	0
Assets	298,076	705,780
Liabilities
2015 notes embedded conversion derivative	0	0
Fixed index annuities - embedded derivatives	0	0
Liabilities	0	0
Quoted Prices in Active Markets (Level 1) [Member] | Interest Rate Caps [Member]
Assets
Interest rate derivative assets	0	0
Quoted Prices in Active Markets (Level 1) [Member] | Interest Rate Swap [Member]
Liabilities
Interest rate derivative liabilities	0	0
Quoted Prices in Active Markets (Level 1) [Member] | Equity Securities [Member]
Assets
Available for sale securities	0	0
Quoted Prices in Active Markets (Level 1) [Member] | United States Government Full Faith and Credit [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	4,300	4,255
Quoted Prices in Active Markets (Level 1) [Member] | United States Government Sponsored Agencies [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Quoted Prices in Active Markets (Level 1) [Member] | United States Municipalities, States and Territories [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Quoted Prices in Active Markets (Level 1) [Member] | Foreign Government Obligations [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Quoted Prices in Active Markets (Level 1) [Member] | Corporate Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	12	11
Quoted Prices in Active Markets (Level 1) [Member] | Residential Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Quoted Prices in Active Markets (Level 1) [Member] | Commercial Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Quoted Prices in Active Markets (Level 1) [Member] | Other Asset Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Significant Other Observable Inputs (Level 2) [Member]
Assets
Derivative assets	610,764	731,113
Cash and cash equivalents	0	0
2015 notes hedges	30,858	30,291
Counterparty collateral	331,035	206,096
Assets	35,181,585	33,418,644
Liabilities
2015 notes embedded conversion derivative	30,858	30,291
Fixed index annuities - embedded derivatives	0	0
Liabilities	34,798	32,935
Significant Other Observable Inputs (Level 2) [Member] | Interest Rate Caps [Member]
Assets
Interest rate derivative assets	2,092	2,778
Significant Other Observable Inputs (Level 2) [Member] | Interest Rate Swap [Member]
Liabilities
Interest rate derivative liabilities	3,940	2,644
Significant Other Observable Inputs (Level 2) [Member] | Equity Securities [Member]
Assets
Available for sale securities	7,849	7,805
Significant Other Observable Inputs (Level 2) [Member] | United States Government Full Faith and Credit [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	34,227	134,205
Significant Other Observable Inputs (Level 2) [Member] | United States Government Sponsored Agencies [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	1,421,364	1,393,890
Significant Other Observable Inputs (Level 2) [Member] | United States Municipalities, States and Territories [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	3,809,862	3,723,309
Significant Other Observable Inputs (Level 2) [Member] | Foreign Government Obligations [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	227,541	193,803
Significant Other Observable Inputs (Level 2) [Member] | Corporate Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	22,751,882	21,490,281
Significant Other Observable Inputs (Level 2) [Member] | Residential Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	1,728,973	1,750,970
Significant Other Observable Inputs (Level 2) [Member] | Commercial Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	3,165,829	2,807,620
Significant Other Observable Inputs (Level 2) [Member] | Other Asset Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	1,059,309	946,483
Significant Unobservable Inputs (Level 3) [Member]
Assets
Derivative assets	0	0
Cash and cash equivalents	0	0
2015 notes hedges	0	0
Counterparty collateral	0	0
Assets	342	375
Liabilities
2015 notes embedded conversion derivative	0	0
Fixed index annuities - embedded derivatives	5,865,171	5,574,653
Liabilities	5,865,171	5,574,653
Significant Unobservable Inputs (Level 3) [Member] | Interest Rate Caps [Member]
Assets
Interest rate derivative assets	0	0
Significant Unobservable Inputs (Level 3) [Member] | Interest Rate Swap [Member]
Liabilities
Interest rate derivative liabilities	0	0
Significant Unobservable Inputs (Level 3) [Member] | Equity Securities [Member]
Assets
Available for sale securities	0	0
Significant Unobservable Inputs (Level 3) [Member] | United States Government Full Faith and Credit [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Significant Unobservable Inputs (Level 3) [Member] | United States Government Sponsored Agencies [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Significant Unobservable Inputs (Level 3) [Member] | United States Municipalities, States and Territories [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Significant Unobservable Inputs (Level 3) [Member] | Foreign Government Obligations [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Significant Unobservable Inputs (Level 3) [Member] | Corporate Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Significant Unobservable Inputs (Level 3) [Member] | Residential Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	342	375
Significant Unobservable Inputs (Level 3) [Member] | Commercial Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	0	0
Significant Unobservable Inputs (Level 3) [Member] | Other Asset Backed Securities [Member] | Fixed Maturity Securities [Member]
Assets
Available for sale securities	$0	$0

Fair_Values_of_Financial_Instr5

Fair Values of Financial Instruments (Reconciliation of Beginning and Ending Balances of Level 3 Assets) (Details) (Fair Value, Measurements, Recurring [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$375	$1,376
Principal returned	-12	-78
Amortization of premium/accretion of discount	-57	-27
Total gains (losses) (realized/unrealized): included in other comprehensive income (loss)	36	-191
Total gains (losses) (realized/unrealized): included in operations	0	0
Ending balance	$342	$1,080

Fair_Values_of_Financial_Instr6

Fair Values of Financial Instruments (Reconciliation of Beginning and Ending Balances of Level 3 Liabilities) (Details) (Fair Value, Measurements, Recurring [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Fair Value, Measurements, Recurring [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$5,574,653	$4,406,163
Premiums less benefits	360,395	371,953
Change in fair value, net	-69,877	-22,203
Ending balance	$5,865,171	$4,755,913

Investments_Narrative_Details

Investments (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
	Securities		Securities
Investments [Abstract]
Fixed income securities with call features, percentage	34.00%
Fixed income securities with call features, currently callable, percentage	0.60%
Fixed income securities with call features, currently callable, amount	$200,000,000
Fixed income securities with call features, callable during next 12 months, percentage	4.00%
Fixed income securities with call features, callable during next 12 months, amount	1,200,000,000
Fixed income securities with call features, not callable until within 6 months of stated maturity, percentage	60.00%
Percentage of fixed maturity portfolio rated investment grade based on NAIC designations	98.00%		98.00%
Number of individual securities with unrealized losses	213		402
Percentage of unrealized losses on fixed maturity securities where securities are rated investment grade	64.00%		78.00%
Investment Holdings [Line Items]
Available for sale securities, amortized cost	31,443,319,000		30,205,046,000
Scheduled principal repayments, calls and tenders for available for sale securities	276,734,000	208,747,000
Fixed Maturity Securities [Member]
Investment Holdings [Line Items]
Scheduled principal repayments, calls and tenders for available for sale securities	107,300,000	152,700,000
Alt-A Sector [Member] | Residential Mortgage Backed Securities [Member]
Investment Holdings [Line Items]
Available for sale securities, number of securities in unrealized loss positions	34
Available for sale securities, amortized cost	235,800,000
Available for sale, fair value	264,600,000
Available For Sale Securities [Member]
Investment Holdings [Line Items]
Proceeds from sales of available for sale securities	169,400,000	56,100,000
Available For Sale Securities [Member] | Fixed Maturity Securities [Member]
Investment Holdings [Line Items]
Available for sale, fair value	34,203,641,000		32,445,202,000
Available For Sale Securities [Member] | Residential Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member]
Investment Holdings [Line Items]
Available for sale, fair value	$1,729,315,000		$1,751,345,000

Investments_Schedule_of_Amorti

Investments (Schedule of Amortized Cost and Fair Value of Fixed Maturity and Equity Securities) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investment Holdings [Line Items]
Held for investment, amortized cost	$76,479	$76,432
Held for investment	82,984	75,838
Fixed Maturity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	31,443,319	30,205,046
Available for sale, gross unrealized gains	2,870,024	2,395,577
Available for sale, gross unrealized losses	-109,702	-155,421
Available for sale, fair value	34,203,641	32,445,202
Equity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	7,511	7,509
Available for sale, gross unrealized gains	338	296
Available for sale, gross unrealized losses	0	0
Available for sale, fair value	7,849	7,805
United States Government Full Faith and Credit [Member] | Fixed Maturity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	37,114	137,710
Available for sale, gross unrealized gains	1,417	765
Available for sale, gross unrealized losses	-4	-15
Available for sale, fair value	38,527	138,460
United States Government Sponsored Agencies [Member] | Fixed Maturity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	1,384,476	1,364,424
Available for sale, gross unrealized gains	45,559	43,399
Available for sale, gross unrealized losses	-8,671	-13,933
Available for sale, fair value	1,421,364	1,393,890
United States Municipalities, States and Territories [Member] | Fixed Maturity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	3,345,258	3,293,551
Available for sale, gross unrealized gains	464,981	430,469
Available for sale, gross unrealized losses	-377	-711
Available for sale, fair value	3,809,862	3,723,309
Foreign Government Obligations [Member] | Fixed Maturity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	210,918	181,128
Available for sale, gross unrealized gains	21,023	16,628
Available for sale, gross unrealized losses	-4,400	-3,953
Available for sale, fair value	227,541	193,803
Corporate Securities [Member] | Fixed Maturity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	20,864,311	19,984,747
Available for sale, gross unrealized gains	1,973,728	1,628,941
Available for sale, gross unrealized losses	-86,145	-123,396
Available for sale, fair value	22,751,894	21,490,292
Corporate Securities [Member] | Fixed Maturity Securities [Member] | Held For Investment Securities [Member]
Investment Holdings [Line Items]
Held for investment, amortized cost	76,479	76,432
Held for investment, gross unrealized gains	6,505	0
Held for investment, gross unrealized losses	0	-594
Held for investment	82,984	75,838
Residential Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	1,571,548	1,616,846
Available for sale, gross unrealized gains	159,281	136,704
Available for sale, gross unrealized losses	-1,514	-2,205
Available for sale, fair value	1,729,315	1,751,345
Commercial Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	3,017,014	2,720,294
Available for sale, gross unrealized gains	149,269	90,649
Available for sale, gross unrealized losses	-454	-3,323
Available for sale, fair value	3,165,829	2,807,620
Other Asset Backed Securities [Member] | Fixed Maturity Securities [Member] | Available For Sale Securities [Member]
Investment Holdings [Line Items]
Available for sale, amortized cost	1,012,680	906,346
Available for sale, gross unrealized gains	54,766	48,022
Available for sale, gross unrealized losses	-8,137	-7,885
Available for sale, fair value	$1,059,309	$946,483

Investments_Fixed_Maturity_Sec

Investments (Fixed Maturity Securities by Contractual Maturity) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis [Abstract]
Available for sale securities, due in one year or less, amortized cost	$79,405
Available for sale securities, due after one year through five years, amortized cost	1,537,898
Available for sale securities, due after five years through ten years, amortized cost	8,936,938
Available for sale securities, due after ten years through twenty years, amortized cost	7,579,323
Available for sale securities, due after twenty years, amortized cost	7,708,513
Available for sale securities, securities with a single maturity date, amortized cost	25,842,077
Available for sale securities, amortized cost	31,443,319	30,205,046
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for sale securities, due in one year or less, fair value	81,179
Available for sale securities, due after one year through five years, fair value	1,706,024
Available for sale securities, due after five years through ten years, fair value	9,293,120
Available for sale securities, due after ten years through twenty years, fair value	8,366,229
Available for sale securities, due after twenty years, fair value	8,802,636
Available for sale securities, securities with a single maturity date, fair value	28,249,188
Available for sale securities, fair value	34,203,641	32,445,202
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	76,479
Held for investment securities, securities with a single maturity date, amortized cost	76,479
Held for investment, amortized cost	76,479	76,432
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	82,984
Held for investment securities, securities with a single maturity date, fair value	82,984
Held for investment	82,984	75,838
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	1,571,548
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for sale securities, securities without a single maturity date, fair value	1,729,315
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	3,017,014
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for sale securities, securities without a single maturity date, fair value	3,165,829
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	1,012,680
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for sale securities, securities without a single maturity date, fair value	1,059,309
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_Gai

Investments (Net Unrealized Gains on Available for Sale Fixed Maturity Securities and Equity Securities Reported as a Separate Component of Stockholders' Equity) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investments [Abstract]
Net unrealized gains on available for sale fixed maturity securities and equity securities	$2,760,660	$2,240,452
Adjustments for assumed changes in amortization of deferred policy acquisition costs and deferred sales inducements	-1,420,347	-1,165,271
Deferred income tax valuation allowance reversal	22,534	22,534
Deferred income tax expense	-469,109	-376,314
Net unrealized gains reported as accumulated other comprehensive income	$893,738	$721,401

Investments_Schedule_of_Credit

Investments (Schedule of Credit Quality of Fixed Maturity Portfolio by NAIC Designation) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investment Holdings [Line Items]
Amortized cost	$31,519,798	$30,281,478
Fair value	34,286,625	32,521,040
NAIC, Class 1 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	19,969,022	19,223,151
Fair value	22,027,864	20,941,634
NAIC, Class 2 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	10,833,446	10,432,593
Fair value	11,565,940	10,981,618
NAIC, Class 3 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	681,662	602,191
Fair value	671,393	583,313
NAIC, Class 4 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	35,082	22,888
Fair value	21,074	14,089
NAIC, Class 5 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	0	0
Fair value	0	0
NAIC, Class 6 Designation [Member]
Investment Holdings [Line Items]
Amortized cost	586	655
Fair value	$354	$386

Investments_Gross_Unrealized_L

Investments (Gross Unrealized Losses on Investments, By Category and Length of Time) (Details) (Fixed Maturity Securities [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	$2,340,660	$2,346,226
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-57,680	-56,929
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	486,894	2,731,950
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-52,022	-98,492
Available for sale securities, continuous unrealized loss position, total, fair value	2,827,554	5,078,176
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-109,702	-155,421
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	508	0
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-4	0
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	0	498
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	0	-15
Available for sale securities, continuous unrealized loss position, total, fair value	508	498
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-4	-15
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	585,574	0
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-8,671	0
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	0	610,339
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	0	-13,933
Available for sale securities, continuous unrealized loss position, total, fair value	585,574	610,339
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-8,671	-13,933
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	50,040	0
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-322	0
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	2,945	27,947
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-55	-711
Available for sale securities, continuous unrealized loss position, total, fair value	52,985	27,947
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-377	-711
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	9,044	14,194
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-1,232	-1,068
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	11,251	11,542
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-3,168	-2,885
Available for sale securities, continuous unrealized loss position, total, fair value	20,295	25,736
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-4,400	-3,953
Corporate Securities [Member] | Finance, Insurance and Real Estate [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available for sale securities, continuous unrealized loss position, less than 12 months, fair value	182,005	253,439
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-1,464	-2,586
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	79,738	399,874
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-10,022	-16,277
Available for sale securities, continuous unrealized loss position, total, fair value	261,743	653,313
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-11,486	-18,863
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	703,225	1,078,089
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-30,909	-35,151
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	235,075	694,088
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-24,455	-35,926
Available for sale securities, continuous unrealized loss position, total, fair value	938,300	1,772,177
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-55,364	-71,077
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	339,510	373,952
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-10,650	-8,185
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	64,467	344,313
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-2,500	-10,153
Available for sale securities, continuous unrealized loss position, total, fair value	403,977	718,265
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-13,150	-18,338
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	71,296	88,766
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-1,058	-2,290
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	23,733	99,427
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-2,727	-3,122
Available for sale securities, continuous unrealized loss position, total, fair value	95,029	188,193
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-3,785	-5,412
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	149,762	131,940
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-1,234	-1,567
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	37,022	277,296
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-1,126	-8,139
Available for sale securities, continuous unrealized loss position, total, fair value	186,784	409,236
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-2,360	-9,706
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
Held for investment securities, continuous unrealized loss position, less than 12 months, unrealized losses		0
Held for investment securities, continuous unrealized loss position, 12 months or longer, fair value		75,838
Held for investment securities, continuous unrealized loss position, 12 months or longer, unrealized losses		-594
Held for investment securities, continuous unrealized loss position, total, fair value		75,838
Held for investment securities, continuous unrealized loss position, total, unrealized losses		-594
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	13,147	22,115
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-149	-1,219
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	7,292	20,427
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-1,365	-986
Available for sale securities, continuous unrealized loss position, total, fair value	20,439	42,542
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-1,514	-2,205
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	110,898	241,637
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-454	-1,344
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	0	187,241
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	0	-1,979
Available for sale securities, continuous unrealized loss position, total, fair value	110,898	428,878
Available for sale securities, continuous unrealized loss position, total, unrealized losses	-454	-3,323
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	125,651	142,094
Available for sale securities, continuous unrealized loss position, less than 12 months, unrealized losses	-1,533	-3,519
Available for sale securities, continuous unrealized loss position, 12 months or longer, fair value	25,371	58,958
Available for sale securities, continuous unrealized loss position, 12 months or longer, unrealized losses	-6,604	-4,366
Available for sale securities, continuous unrealized loss position, total, fair value	151,022	201,052
Available for sale securities, continuous unrealized loss position, total, unrealized losses	($8,137)	($7,885)

Investments_Changes_in_Net_Unr

Investments (Changes in Net Unrealized Gains on Investments) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Investment Holdings [Line Items]
Fixed maturity securities held for investment carried at amortized cost	$7,099	$4,037
Investments carried at fair value, available for sale	520,208	977,118
Adjustment for effect on other balance sheet accounts:
Deferred policy acquisition costs and deferred sales inducements	-255,076	-536,752
Deferred income tax asset/liability	-92,795	-154,127
Total adjustment for effect on other balance sheet accounts	-347,871	-690,879
Change in net unrealized gains on investments carried at fair value	172,337	286,239
Fixed Maturity Securities [Member]
Investment Holdings [Line Items]
Investments carried at fair value, available for sale	520,166	977,131
Equity Securities [Member]
Investment Holdings [Line Items]
Investments carried at fair value, available for sale	$42	($13)

Investments_Net_Realized_Gains

Investments (Net Realized Gains (Losses) on Invesments, Excluding Other Than Temporary Impairments) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Gain (Loss) on Investments [Line Items]
Net realized gains (losses) on investments, excluding other than temporary impairment (OTTI) losses	$4,879	($714)
Fixed Maturity Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross realized gains	2,288	184
Gross realized losses	-289	-691
Gross realized gains (losses), excluding other than temporary impairments	1,999	-507
Other Investments [Member]
Gain (Loss) on Investments [Line Items]
Gain on sale of real estate	838	756
Loss on sale of real estate	-382	0
Impairment losses on real estate	-629	-799
Gain (loss) on other investments	-173	-43
Mortgage Loans on Real Estate [Member]
Gain (Loss) on Investments [Line Items]
Decrease (increase) in allowance for credit losses	1,798	-164
Recovery of specific allowance	1,255	0
Change in allowance for credit losses and recoveries	$3,053	($164)

Investments_Significant_Assump

Investments (Significant Assumptions in Determining Credit Loss Component of Other Than Temporary Impairment on Residential Mortgage Backed Securities) (Details) (Residential Mortgage Backed Securities [Member], Prime Sector [Member], Vintage Year 2006 [Member])	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate	6.50%	6.50%
Default rate	14.00%	11.00%
Loss severity	40.00%	50.00%
Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Discount rate	6.50%	7.40%
Default rate	14.00%	12.00%
Loss severity	40.00%	50.00%

Investments_Other_Than_Tempora

Investments (Other Than Temporary Impairments by Asset Type) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Other than Temporary Impairment Losses, Investments [Abstract]
Total OTTI losses	($132)	$0
Portion of OTTI losses recognized from other comprehensive income	0	-905
Net OTTI losses recognized in operations	-132	-905
Residential Mortgage Backed Securities [Member]
Other than Temporary Impairment Losses, Investments [Abstract]
Other than temporary impairment, number of securities	1	2
Total OTTI losses	-132	0
Portion of OTTI losses recognized from other comprehensive income	0	-905
Net OTTI losses recognized in operations	($132)	($905)

Investments_Cumulative_Credit_

Investments (Cumulative Credit Loss Portion of Other Than Temporary Impairment Recognized in Operations) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Investments [Abstract]
Cumulative credit loss at beginning of period	($127,050)	($125,960)
Credit losses on securities for which OTTI has not previously been recognized	-132	0
Additional credit losses on securities for which OTTI has previously been recognized	0	-905
Accumulated losses on securities that were disposed of during the period	0	0
Cumulative credit loss at end of period	($127,182)	($126,865)

Investments_Cumulative_Noncred

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 $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investment Holdings [Line Items]
Amortized cost	$551,990	$569,508
OTTI recognized in other comprehensive income	-173,494	-173,494
Change in fair value since OTTI was recognized	219,823	215,636
Fair value	598,319	611,650
Fixed Maturity Securities [Member] | Corporate Securities [Member]
Investment Holdings [Line Items]
Amortized cost	0	0
OTTI recognized in other comprehensive income	0	0
Change in fair value since OTTI was recognized	12	11
Fair value	12	11
Fixed Maturity Securities [Member] | Residential Mortgage Backed Securities [Member]
Investment Holdings [Line Items]
Amortized cost	551,990	569,508
OTTI recognized in other comprehensive income	-173,494	-173,494
Change in fair value since OTTI was recognized	219,811	215,625
Fair value	$598,307	$611,639

Mortgage_Loans_on_Real_Estate_1

Mortgage Loans on Real Estate (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
	loans	loans
	portfolio_segment
Mortgage Loans on Real Estate [Abstract]
Mortgage loans on real estate	$2,433,757,000		$2,434,580,000
Commitments outstanding	87,000,000
Number of portfolio segments that make up financing receivables	1
Number of mortgage loans satisfied by foreclosure	0	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, delinquent status	60 days
Number of days past due, non-accrual status	90 days
Outstanding principal of loans in a non-accrual status	$4,800,000		$6,000,000

Mortgage_Loans_on_Real_Estate_2

Mortgage Loans on Real Estate (Summary of Mortgage Loan Portfolio) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Mortgage Loans on Real Estate [Abstract]
Principal outstanding	$2,453,692	$2,457,721
Loan loss allowance	-19,452	-22,633
Deferred prepayment fees	-483	-508
Mortgage loans on real estate	$2,433,757	$2,434,580

Mortgage_Loans_on_Real_Estate_3

Mortgage Loans on Real Estate (Mortgage Loan Portfolio Summarized by Geographic Region and Property Type) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$2,453,692	$2,457,721
Percent	100.00%	100.00%
Office [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	457,690	484,585
Percent	18.70%	19.70%
Medical Office [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	87,104	88,275
Percent	3.50%	3.60%
Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	712,473	711,775
Percent	29.00%	29.00%
Industrial/Warehouse [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	664,136	649,425
Percent	27.10%	26.40%
Hotel [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	22,519	30,640
Percent	0.90%	1.30%
Apartment [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	353,693	335,087
Percent	14.40%	13.60%
Mixed Use/Other [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	156,077	157,934
Percent	6.40%	6.40%
East [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	714,054	701,638
Percent	29.10%	28.50%
Middle Atlantic [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	164,954	166,249
Percent	6.70%	6.80%
Mountain [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	279,605	279,075
Percent	11.40%	11.40%
New England [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	9,589	12,280
Percent	0.40%	0.50%
Pacific [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	301,176	302,307
Percent	12.30%	12.30%
South Atlantic [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	475,064	471,849
Percent	19.40%	19.20%
West North Central [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	341,682	349,028
Percent	13.90%	14.20%
West South Central [Member]
Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$167,568	$175,295
Percent	6.80%	7.10%

Mortgage_Loans_on_Real_Estate_4

Mortgage Loans on Real Estate (Allowance for Loan Losses Rollforward) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning allowance balance			($22,633)
Ending allowance balance	-19,452		-22,633
Specific Allowance [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning allowance balance	-12,333	-16,847
Charge-offs	128	949
Recoveries	1,255	0
Change in provision for credit losses	-1,502	-564
Ending allowance balance	-12,452	-16,462
General Allowance [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning allowance balance	-10,300	-9,200
Charge-offs	0	0
Recoveries	0	0
Change in provision for credit losses	3,300	400
Ending allowance balance	($7,000)	($8,800)

Mortgage_Loans_on_Real_Estate_5

Mortgage Loans on Real Estate (Impaired Mortgage Loans on Real Estate by Basis of Impairment) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Mortgage Loans on Real Estate [Abstract]
Individually evaluated for impairment	$30,763	$29,116
Collectively evaluated for impairment	2,422,929	2,428,605
Principal outstanding	$2,453,692	$2,457,721

Mortgage_Loans_on_Real_Estate_6

Mortgage Loans on Real Estate (Real Estate Owned) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Mortgage Loans on Real Estate [Abstract]
Real estate owned at beginning of period	$20,238	$22,844
Real estate acquired in satisfaction of mortgage loans	0	1,713
Sales	-4,899	-3,030
Impairments	-629	-799
Depreciation	-99	-136
Real estate owned at end of period	$14,611	$20,592

Mortgage_Loans_on_Real_Estate_7

Mortgage Loans on Real Estate (Mortgage Loans by Credit Quality Indicator) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Mortgage Loans on Real Estate [Abstract]
Performing	$2,436,604	$2,451,760
In workout	9,928	0
Delinquent	2,316	0
Collateral dependent	4,844	5,961
Principal outstanding	$2,453,692	$2,457,721

Mortgage_Loans_on_Real_Estate_8

Mortgage Loans on Real Estate (Schedule of Financing Receivables Past Due) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Mortgage Loans on Real Estate [Abstract]
30 - 59 days	$11,281	$0
60 to 89 days	2,316	0
90 days and over	0	0
Total past due	13,597	0
Current	2,435,251	2,451,760
Collateral dependent receivables	4,844	5,961
Principal outstanding	$2,453,692	$2,457,721

Mortgage_Loans_on_Real_Estate_9

Mortgage Loans on Real Estate (Schedule of Impaired Financing Receivables) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Mortgage loans with an allowance, recorded investment	$18,311		$16,783
Mortgage loans with no related allowance, recorded investment	13,087		2,656
Impaired mortgage loans, recorded investment	31,398		19,439
Mortgage loans with an allowance, unpaid principal balance	30,763		29,116
Mortgage loans with no related allowance, unpaid principal balance	13,087		2,656
Impaired mortgage loans, unpaid principal balance	43,850		31,772
Mortgage loans with an allowance, related allowance	-12,452		-12,333
Mortgage loans with an allowance, average recorded investment	19,158	29,884
Mortgage loans with no related allowance, average recorded investment	13,107	3,456
Impaired mortgage loans, average recorded investment	32,265	33,340
Mortgage loans with an allowance, interest income recognized	451	508
Mortgage loans with no related allowance, interest income recognized	159	351
Impaired mortgage loans, interest income reoognized	$610	$859

Recovered_Sheet1

Mortgage Loans on Real Estate (Troubled Debt Restructurings) (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
	loans	loans
Financing Receivable, Modifications [Line Items]
Number of TDRs	10	9
Principal balance outstanding	$22,186	$18,533
Specific loan loss allowance	-4,505	-5,758
Net carrying amount	17,681	12,775
South Atlantic [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs	6	7
Principal balance outstanding	11,033	14,475
Specific loan loss allowance	-2,992	-4,244
Net carrying amount	8,041	10,231
East North Central [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs	2	1
Principal balance outstanding	3,363	2,177
Specific loan loss allowance	-467	-467
Net carrying amount	2,896	1,710
West North Central [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs	2	1
Principal balance outstanding	7,790	1,881
Specific loan loss allowance	-1,046	-1,047
Net carrying amount	$6,744	$834

Derivative_Instruments_Narrati

Derivative Instruments (Narrative) (Details) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2010	Mar. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Derivative collateral		$541.70	$743
Credit risk, maximum exposure		89.1	47.4
2015 Notes Hedges [Member]
Derivative [Line Items]
Number of counterparties	2
Derivative, conversion spread, shares of common stock	16	1.8	1.8
Derivative asset, strike price	$12.50	$12.25	$12.25
2015 Warrants [Member]
Derivative [Line Items]
Warrants, number of securities called by warrants	16	1.8	1.8
Warrants, strike price	$16	$15.68	$15.68
Proceeds from issuance of warrants	15.6
September 2015 Notes [Member]
Derivative [Line Items]
Principal amount of convertible senior notes payable at issuance	200
Debt instrument, interest rate, stated percentage		3.50%
SunTrust [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Interest rate swaps and caps, duration		7 years
Collateral on deposit		$1.70
SunTrust [Member] | Three Month London Interbank Offered Rate (LIBOR) [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, cap interest rate		2.50%
Call Options [Member]
Derivative [Line Items]
Investment maturity period		1 year

Derivative_Instruments_Fair_Va

Derivative Instruments (Fair Value of Derivative Instruments as Presented in the Consolidated Balance Sheets) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]
Derivative assets	$610,764	$731,113
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	643,714	764,182
Derivative liabilities	5,899,969	5,607,588
Call Options [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	610,764	731,113
2015 Notes Hedges [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	30,858	30,291
Interest Rate Caps [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	2,092	2,778
Fixed Index Annuities - Embedded Derivatives [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	5,865,171	5,574,653
2015 Notes Embedded Conversion Derivative [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	30,858	30,291
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	$3,940	$2,644

Derivative_Instruments_Change_

Derivative Instruments (Change in Fair Value of Derivatives Included in the Consolidated Statement of Operations) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of derivatives	($31,100)	$48,493
Change in fair value of embedded derivatives	51,213	92,619
Call Options [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of derivatives	-29,220	71,473
2015 Notes Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of derivatives	567	-20,401
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of derivatives	-1,761	-1,402
Interest Rate Caps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of derivatives	-686	-1,177
Fixed Index Annuities - Embedded Derivatives [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of embedded derivatives	50,646	113,020
2015 Notes Embedded Conversion Derivative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of embedded derivatives	$567	($20,401)

Derivative_Instruments_Derivat

Derivative Instruments (Derivative Call Options, Notional Amount and Fair Value, by Counterparty) (Details) (Call Options [Member], Not Designated as Hedging Instrument [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Derivative [Line Items]
Notional amount	$25,157,584	$23,956,444
Derivative instruments	610,764	731,113
Bank of America [Member]
Derivative [Line Items]
Notional amount	3,152,382	2,114,812
Derivative instruments	76,489	62,932
Barclays [Member]
Derivative [Line Items]
Notional amount	4,014,576	4,083,259
Derivative instruments	122,621	135,609
BNP Paribas [Member]
Derivative [Line Items]
Notional amount	1,379,283	1,321,136
Derivative instruments	37,110	42,644
Citibank, N.A. [Member]
Derivative [Line Items]
Notional amount	2,928,152	3,190,204
Derivative instruments	53,952	96,759
Credit Suisse [Member]
Derivative [Line Items]
Notional amount	1,825,842	2,354,811
Derivative instruments	40,812	75,381
Deutsche Bank [Member]
Derivative [Line Items]
Notional amount	2,812,033	2,682,960
Derivative instruments	49,973	64,028
HSBC [Member]
Derivative [Line Items]
Notional amount	21,141	38,599
Derivative instruments	922	1,767
J.P. Morgan [Member]
Derivative [Line Items]
Notional amount	343,720	401,804
Derivative instruments	6,068	13,488
Morgan Stanley [Member]
Derivative [Line Items]
Notional amount	2,758,628	2,605,687
Derivative instruments	59,904	77,106
Royal Bank of Canada [Member]
Derivative [Line Items]
Notional amount	1,496,512	1,364,362
Derivative instruments	42,056	41,717
SunTrust [Member]
Derivative [Line Items]
Notional amount	617,049	248,622
Derivative instruments	12,728	5,405
Wells Fargo [Member]
Derivative [Line Items]
Notional amount	3,808,266	3,550,188
Derivative instruments	$108,129	$114,277

Derivative_Instruments_Interes

Derivative Instruments (Interest Rate Swap) (Details) (Interest Rate Swap [Member], Interest Rate Swap, Maturity Date, March 15, 2021, 2.415% [Member], SunTrust [Member], Not Designated as Hedging Instrument [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Interest Rate Swap [Member] | Interest Rate Swap, Maturity Date, March 15, 2021, 2.415% [Member] | SunTrust [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Notional amount	$85,500
Pay rate	2.42%
Derivative liabilities	($3,940)	($2,644)

Derivative_Instruments_Interes1

Derivative Instruments (Interest Rate Caps) (Details) (Interest Rate Caps [Member], SunTrust [Member], Not Designated as Hedging Instrument [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Derivative [Line Items]
Notional amount	$79,000
Derivative assets	2,092	2,778
Interest Rate Caps, Maturity Date, July 7, 2021, 2.50% [Member]
Derivative [Line Items]
Notional amount	40,000
Cap rate	2.50%
Derivative assets	1,052	1,398
Interest Rate Caps, Maturity Date, July 8, 2021, 2.50% [Member]
Derivative [Line Items]
Notional amount	12,000
Cap rate	2.50%
Derivative assets	316	420
Interest Rate Caps, Maturity Date, July 29, 2021, 2.50% [Member]
Derivative [Line Items]
Notional amount	27,000
Cap rate	2.50%
Derivative assets	$724	$960

Notes_Payable_Liability_and_Eq

Notes Payable (Liability and Equity Components of Convertible Senior Notes) (Details) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Debt Instrument [Line Items]
Interest expense on convertible notes	$7,339	$10,264
September 2015 Notes [Member]
Debt Instrument [Line Items]
Principal amount of liability component	22,377		22,377
Unamortized discount	-458		-698
Net carrying amount of liability component	21,919		21,679
Amount by which the if-converted value exceeds principal	30,389		30,497
Interest rate, effective percentage	8.90%
Convertible Debt [Member]
Debt Instrument [Line Items]
Interest expense on convertible notes	$500	$3,400

Notes_Payable_Line_of_Credit_N

Notes Payable (Line of Credit Narrative) (Details) (2013 Line of Credit [Member], USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
	occasions
	banks
	guarantor
2013 Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$140,000,000
Line of credit, number of banks in agreement	5
Line of credit, interest rate, floating, applicable margin	1.00%
Line of credit, interest rate, floating, adjusted LIBOR	2.00%
Line of credit, unused capacity, commitment fee percentage	0.35%
Minimum risk-based capital ratio	275.00%
Maximum debt to capital ratio	0.35
Minimum capital to be retained	80.00%
Minimum portion of net income to be retained	50.00%
Minimum capital contributions to be retained	50.00%
Line of credit, number of occasions borrowing capacity can be increased	3
Line of credit, additional borrowing capacity, aggregate amount	50,000,000
Line of credit, maturity date extension available, years	1 year
Line of credit, number of guarantors	0
Line of credit, amount outstanding	0	0
Cash in excess of amount required by covenants	$534,000,000

Notes_Payable_Repurchase_Agree

Notes Payable (Repurchase Agreements Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Debt Disclosure [Abstract]
Repurchase agreement, maximum amount borrowed	$40.60	$138.70
Repurchase agreement, average borrowings	$1.90	$27.50
Repurchase agreement, weighted average interest rate	0.39%	0.15%

Commitments_and_Contingencies_

Commitments and Contingencies (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2015	Dec. 31, 2013	Sep. 30, 2012
Commitments and Contingencies Disclosure [Abstract]
Estimated litigation liability		$11.10	$21.20	$17.50
Change in estimated litigation liability	-2.3
Legal fees paid	7.8
Unfunded commitments to limited partnerships		28.6
Unfunded commitments to secured bank loans		$11.20

Earnings_Loss_Per_Share_Schedu

Earnings (Loss) Per Share (Schedule of Earnings (Loss) Per Share, Basic and Diluted) (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Earnings Per Share, Basic and Diluted [Line Items]
Net income (loss) - numerator for earnings (loss) per common share	$5,903		($9,753)
Weighted average common shares outstanding (shares)	77,041,704	[1]	72,518,574	[1]
Effect of dilutive securities: 2015 warrants (shares)	806,485		2,372,404
Denominator for earnings (loss) per common share - assuming dilution (shares)	79,118,034		79,615,779
Earnings (loss) per common share	$0.08		($0.13)
Earnings (loss) per common share - assuming dilution	$0.07		($0.13)
Convertible Senior Notes [Member]
Earnings Per Share, Basic and Diluted [Line Items]
Effect of dilutive securities: convertible senior notes (shares)	0		3,400,986
Stock Options and Deferred Compensation Agreements [Member]
Earnings Per Share, Basic and Diluted [Line Items]
Effect of dilutive securities: share-based payment arrangements (shares)	1,159,334		1,287,267
Restricted Stock and Restricted Stock Units [Member]
Earnings Per Share, Basic and Diluted [Line Items]
Effect of dilutive securities: share-based payment arrangements (shares)	110,511		36,548
[1]	Weighted average common shares outstanding include shares vested under the NMO Deferred Compensation Plan and exclude unallocated shares held by the ESOP.

Earnings_Loss_Per_Share_Schedu1

Earnings (Loss) Per Share (Schedule of Antidilutive Securities Excluded from Computation of Earnings (Loss) Per Share) (Details) (Stock Options [Member], USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares	0	1,277,650
Minimum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Range of exercise prices	0	24.79
Maximum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Range of exercise prices	0	24.79