SCHEDULE II-CONDENSED FINANCIAL INFORMATION OF REGISTRANT (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended									12 Months Ended
	Dec. 31, 2012		Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
ASSETS
Fixed maturities (amortized cost, 2012-$137,330; 2011-$421,250)	$ 4,227,339					$ 5,820,900				$ 4,227,339	$ 5,820,900
Cash and cash equivalents	1,027,625					995,799				1,027,625	995,799	1,304,154
Accrued investment income	27,243					55,666				27,243	55,666
Other assets	62,465					59,897				62,465	59,897
Total assets	5,574,324					7,216,230				5,574,324	7,216,230
Liabilities:
Senior notes	99,910					170,515				99,910	170,515
Convertible senior notes	345,000					345,000				345,000	345,000
Convertible junior debentures	379,609					344,422				379,609	344,422
Total liabilities	5,377,384					6,019,415				5,377,384	6,019,415
Shareholders' equity
Common stock, (one dollar par value, shares authorized 680,000; shares issued 2012 and 2011 - 205,047; shares outstanding 2012 - 202,032; 2011 - 201,172)	205,047					205,047				205,047	205,047
Paid-in capital	1,135,296					1,135,821				1,135,296	1,135,821
Treasury stock (shares at cost 2012 - 3,015; 2011 - 3,875)	(104,959)					(162,542)				(104,959)	(162,542)
Accumulated other comprehensive (loss) income, net of tax	(48,163)					30,124				(48,163)	30,124
Retained deficit	(990,281)					(11,635)				(990,281)	(11,635)
Total shareholders' equity	196,940					1,196,815				196,940	1,196,815
Total liabilities and shareholders' equity	5,574,324					7,216,230				5,574,324	7,216,230
Parenthetical information [Abstract]
Fixed maturities, amortized cost	4,185,937					5,700,894				4,185,937	5,700,894
Common stock, par value (in dollars per share)	$ 1					$ 1				$ 1	$ 1
Common stock, shares authorized (in shares)	680,000					460,000				680,000	460,000
Common stock, shares issued (in shares)	205,047					205,047				205,047	205,047
Common stock, shares outstanding (in shares)	202,032					201,172				202,032	201,172
Treasury stock, shares at cost (in shares)	3,015					3,875				3,015	3,875
Revenues:
Investment income, net of expenses	21,660	[1]	30,394	32,178	37,408	40,339	48,898	55,490	56,543	121,640	201,270	247,253
Realized investment gains, net										197,719	143,430	102,581
Other income										28,145	36,459	11,588
Total revenues										1,378,364	1,504,279	1,520,525
Expenses:
Interest expense	25,327	[1]	24,478	24,912	24,627	25,142	25,761	26,326	26,042	99,344	103,271	98,589
Total expenses										2,307,008	1,988,578	1,879,925
Loss before income taxes										(928,644)	(484,299)	(359,400)
Benefit from income taxes										(1,565)	1,593	4,335
Net loss	(386,691)	[1]	(246,942)	(273,891)	(19,555)	(135,294)	(165,205)	(151,732)	(33,661)	(927,079)	(485,892)	(363,735)
Other comprehensive (loss) income, net										(78,287)	7,988	(52,019)
Comprehensive loss										(1,005,366)	(477,904)	(415,754)
Cash flows from operating activities:
Net loss	(386,691)	[1]	(246,942)	(273,891)	(19,555)	(135,294)	(165,205)	(151,732)	(33,661)	(927,079)	(485,892)	(363,735)
Adjustments to reconcile net loss to net cash used in operating activities:
Other										(21,026)	(14,218)	(13,646)
Change in certain assets and liabilities:
Accrued investment income										28,423	14,639	9,523
Net cash used in operating activities										(1,568,600)	(1,883,851)	(875,430)
Cash flows from investing activities:
Purchase of fixed maturities										(5,025,204)	(4,393,471)	(5,225,794)
Sale of fixed maturities										5,216,934	4,742,213	4,287,312
Net cash used in investing activities										1,653,533	1,754,217	(111,904)
Cash flows from financing activities:
Common stock shares issued										0	0	772,376
Net cash (used in) provided by financing activities										(53,107)	(178,721)	1,105,749
Net increase (decrease) in cash and cash equivalents										31,826	(308,355)	118,415
Cash and cash equivalents at beginning of year					995,799				1,304,154	995,799	1,304,154	1,185,739
Cash and cash equivalents at end of year	1,027,625					995,799				1,027,625	995,799	1,304,154
Dividends and Dividend Restrictions [Abstract]
Percentage of statutory policyholders' surplus used to determine maximum allowable dividends (in hundredths)	10.00%									10.00%
Parent Company [Member]
ASSETS
Fixed maturities (amortized cost, 2012-$137,330; 2011-$421,250)	139,019					428,985				139,019	428,985
Cash and cash equivalents	175,880					57,636				175,880	57,636	58,380
Investment in subsidiaries, at equity in net assets	709,946					1,544,017				709,946	1,544,017
Accounts receivable - affiliates	669					0				669	0
Income taxes receivable	17,955					23,864				17,955	23,864
Accrued investment income	1,018					3,720				1,018	3,720
Other assets	7,431					11,785				7,431	11,785
Total assets	1,051,918					2,070,007				1,051,918	2,070,007
Liabilities:
Senior notes	99,910					170,515				99,910	170,515
Convertible senior notes	345,000					345,000				345,000	345,000
Convertible junior debentures	379,609					344,422				379,609	344,422
Accounts payable - affiliates	0					84				0	84
Accrued interest	30,459					13,171				30,459	13,171
Total liabilities	854,978					873,192				854,978	873,192
Shareholders' equity
Common stock, (one dollar par value, shares authorized 680,000; shares issued 2012 and 2011 - 205,047; shares outstanding 2012 - 202,032; 2011 - 201,172)	205,047					205,047				205,047	205,047
Paid-in capital	1,135,296					1,135,821				1,135,296	1,135,821
Treasury stock (shares at cost 2012 - 3,015; 2011 - 3,875)	(104,959)					(162,542)				(104,959)	(162,542)
Accumulated other comprehensive (loss) income, net of tax	(48,163)					30,124				(48,163)	30,124
Retained deficit	(990,281)					(11,635)				(990,281)	(11,635)
Total shareholders' equity	196,940					1,196,815				196,940	1,196,815
Total liabilities and shareholders' equity	1,051,918					2,070,007				1,051,918	2,070,007
Parenthetical information [Abstract]
Fixed maturities, amortized cost	137,330					421,250				137,330	421,250
Common stock, par value (in dollars per share)	$ 1					$ 1				$ 1	$ 1
Common stock, shares authorized (in shares)	680,000					460,000				680,000	460,000
Common stock, shares issued (in shares)	205,047					205,047				205,047	205,047
Common stock, shares outstanding (in shares)	202,032					201,172				202,032	201,172
Treasury stock, shares at cost (in shares)	3,015					3,875				3,015	3,875
Revenues:
Investment income, net of expenses										6,921	15,693	5,573
Realized investment gains, net										9,895	4,724	163
Other income										17,775	27,688	0
Total revenues										34,591	48,105	5,736
Expenses:
Operating expenses										2,227	(133)	2,116
Interest expense										99,344	103,271	98,589
Total expenses										101,571	103,138	100,705
Loss before income taxes										(66,980)	(55,033)	(94,969)
Benefit from income taxes										0	(6,872)	(2,078)
Equity in undistributed net loss of subsidiaries										(860,099)	(437,731)	(270,844)
Net loss										(927,079)	(485,892)	(363,735)
Other comprehensive (loss) income, net										(78,287)	7,988	(52,019)
Comprehensive loss										(1,005,366)	(477,904)	(415,754)
Cash flows from operating activities:
Net loss										(927,079)	(485,892)	(363,735)
Adjustments to reconcile net loss to net cash used in operating activities:
Equity in undistributed net loss of subsidiaries										860,099	437,731	270,844
Other										23,765	7,378	40,638
Change in certain assets and liabilities:
Accounts receivable - affiliates										(753)	770	658
Income taxes receivable										5,909	(2,452)	6,330
Accrued investment income										2,702	1,890	(5,474)
Accrued interest										17,288	(2,438)	(33,795)
Net cash used in operating activities										(18,069)	(43,013)	(84,534)
Cash flows from investing activities:
Transactions with subsidiaries										(100,000)	(200,000)	(200,000)
Purchase of fixed maturities										(120,181)	(130,503)	(977,408)
Sale of fixed maturities										409,601	551,493	135,413
Net cash used in investing activities										189,420	220,990	(1,041,995)
Cash flows from financing activities:
Repayment of long-term debt										(53,107)	(178,721)	(1,000)
Net proceeds from convertible senior notes										0	0	334,373
Common stock shares issued										0	0	772,376
Net cash (used in) provided by financing activities										(53,107)	(178,721)	1,105,749
Net increase (decrease) in cash and cash equivalents										118,244	(744)	(20,780)
Cash and cash equivalents at beginning of year					57,636				58,380	57,636	58,380	79,160
Cash and cash equivalents at end of year	$ 175,880					$ 57,636				$ 175,880	$ 57,636	$ 58,380
Dividends and Dividend Restrictions [Abstract]
Percentage of statutory policyholders' surplus used to determine maximum allowable dividends (in hundredths)	10.00%									10.00%

[1] The results for the fourth quarter of 2012 include a loss of approximately $267 million related to our settlement with Freddie Mac and approximately $100 million related to our probable rescission settlement agreements. See Note 20 - "Litigation and Contingencies".