Quarterly Information (unaudited) Quarterly Information (unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Apr. 30, 2013	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014
Goodwill, Impairment Loss		$ 514,511
Successor [Member]
Gross Premiums Written	$ (18,732)	(8,710)	$ (11,192)	$ 1,062	$ (223,358)	$ (13,700)	$ (45,486)	$ (5,766)		$ (80,309)	$ (37,572)	$ (288,310)
Premiums Earned, Net, Financial Guarantee Insurance Contracts	114,463	71,535	60,879	65,718	33,969	64,831	65,013	82,547		213,518	312,595	246,360
Net Investment Income	64,358	64,195	64,753	72,983	66,471	83,581	80,093	70,801		146,446	266,289	300,946
Net Other Than Temporary Impairment Losses Recognized In Earnings	(12,370)	(9,150)	(1,020)	(3,119)	(1,637)	(5,011)	(8,754)	(10,392)
Net realized investment gains	2,622	2,106	(5,353)	54,101	29,376	10,045	3,067	16,289		4,467	53,476	58,777
Gain (Loss) on Derivative Instruments, Net, Pretax	(3,045)	36,952	10,293	(2,499)	10,327	7,416	(1,219)	7,382		192,869	41,701	23,906
Gain (Loss) on Derivative Instruments Held for Trading Purposes, Net	9,314	(65,083)	50,999	(37,774)	(63,576)	(15,685)	(47,985)	(53,841)		114,771	(42,544)	(181,087)
Net realized gains (losses) on extinguishment of debt	0	1,420	(1,246)	(93)	(74,724)	0	0	0		0	81	(74,724)
Variable Interest Entity, Measure of Activity, Operating Income or Loss	(6,561)	(21,435)	52,603	6,962	2,362	9,116	(38,148)	(5,542)		(48,623)	31,569	(32,212)
Policyholder Benefits and Claims Incurred, Net, Financial Guarantee	(337,065)	(133,213)	(147,477)	(150,952)	(552,182)	(28,698)	175,317	(140,011)		(185,138)	(768,707)	(545,574)
Amortization of insurance intangible assets	54,357	39,680	38,088	37,432	41,952	41,908	36,256	31,714		99,658	169,557	151,830
Other Underwriting Expense	27,300	25,006	25,873	24,523	26,142	25,513	24,033	25,786		68,769	102,702	101,474
Interest Expense, Debt	30,557	29,899	28,173	27,908	31,354	31,841	31,953	32,328		84,950	116,537	127,476
Goodwill, Impairment Loss											514,511	0
Reorganization items	0	0	0	0	0	2	186	23		493	0	211
Pre-tax (loss) income from continuing operations	395,576	(388,193)	286,095	216,580	459,594	84,773	(210,412)	159,298		512,316	510,058	493,253
Net Income (Loss) Attributable to Parent	$ 386,984	$ (390,987)	$ 282,695	$ 214,711	$ 453,584	$ 82,450	$ (207,905)	$ 155,942		$ 505,219	$ 493,403	$ 484,071
Earnings Per Share, Basic	$ 8.57	$ (8.66)	$ 6.26	$ 4.75	$ 10.05	$ 1.83	$ (4.61)	$ 3.46		$ 11.23	$ 10.92	$ 10.73
Earnings Per Share, Diluted	$ 8.56	$ (8.66)	$ 6.05	$ 4.57	$ 9.73	$ 1.77	$ (4.61)	$ 3.31		$ 10.91	$ 10.72	$ 10.31
Predecessor [Member]
Gross Premiums Written									$ (14,125)
Premiums Earned, Net, Financial Guarantee Insurance Contracts									130,000
Net Investment Income									116,740
Net realized investment gains									53,305
Gain (Loss) on Derivative Instruments, Net, Pretax									(60,384)
Gain (Loss) on Derivative Instruments Held for Trading Purposes, Net									(33,735)
Net realized gains (losses) on extinguishment of debt									0
Variable Interest Entity, Measure of Activity, Operating Income or Loss									426,566
Policyholder Benefits and Claims Incurred, Net, Financial Guarantee									(38,056)
Amortization of insurance intangible assets									0
Other Underwriting Expense									44,566
Interest Expense, Debt									31,025
Reorganization items									(2,745,180)
Pre-tax (loss) income from continuing operations									3,348,033
Net Income (Loss) Attributable to Parent									$ 3,349,049
Earnings Per Share, Basic									$ 11.07
Earnings Per Share, Diluted									$ 11.07