Quarterly Information (unaudited) Quarterly Information (unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	2 Months Ended	3 Months Ended						8 Months Ended	12 Months Ended	1 Months Ended	3 Months Ended	4 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2014	Apr. 30, 2013	Mar. 31, 2013	Apr. 30, 2013	Dec. 31, 2012
Successor [Member]
Gross Premiums Written	$ (34,081)	$ (223,358)	$ (13,700)	$ (45,486)	$ (5,766)	$ (11,848)	$ (34,380)	$ (80,309)	$ (288,310)
Premiums Earned, Net, Financial Guarantee Insurance Contracts	58,039	33,969	64,831	65,013	82,547	84,530	70,949	213,518	246,360
Net Investment Income	26,196	66,471	83,581	80,093	70,801	68,124	52,126	146,446	300,946
Net Other Than Temporary Impairment Losses Recognized In Earnings	(2,002)	(1,637)	(5,011)	(8,754)	(10,392)	(6,725)	(38,037)
Net realized investment gains	18,472	29,376	10,045	3,067	16,289	(3,695)	(10,310)	4,467	58,777
Gain (Loss) on Derivative Instruments, Net, Pretax	51,220	10,327	7,416	(1,219)	7,382	110,455	31,194	192,869	23,906
Gain (Loss) on Derivative Instruments Held for Trading Purposes, Net	83,713	(63,576)	(15,685)	(47,985)	(53,841)	18,686	12,372	114,771	(181,087)
Net realized losses on extinguishment of debt		(74,724)	0	0	0			0	(74,724)
Variable Interest Entity, Measure of Activity, Operating Income or Loss	4,598	2,362	9,116	(38,148)	(5,542)	(108,330)	55,109	(48,623)	(32,212)
Policyholder Benefits and Claims Incurred, Net, Financial Guarantee	(26,117)	(552,182)	(28,698)	175,317	(140,011)	(4,731)	(154,290)	(185,138)	(545,574)
Amortization of insurance intangible assets	24,952	41,952	41,908	36,256	31,714	37,233	37,473	99,658	151,830
Other Underwriting Expense	16,217	26,142	25,513	24,033	25,786	27,505	25,047	68,769	101,474
Interest Expense, Debt	21,144	31,354	31,841	31,953	32,328	31,989	31,817	84,950	127,476
Reorganization items	424	0	2	186	23	65	4	493	211
Pre-tax (loss) income from continuing operations	205,795	459,594	84,773	(210,412)	159,298	74,920	231,601	512,316	493,253
Net Income (Loss) Attributable to Parent	205,681	453,584	82,450	(207,905)	155,942	68,563	230,975	505,219	484,071
Earnings Per Share, Basic	$ 4.57	$ 10.05	$ 1.83	$ (4.61)	$ 3.46	$ 1.52	$ 5.13	$ 11.23	$ 10.73
Earnings Per Share, Diluted	$ 4.42	$ 9.73	$ 1.77	$ (4.61)	$ 3.31	$ 1.49	$ 4.98	$ 10.91	$ 10.31
Predecessor [Member]
Gross Premiums Written										(10,595)	(3,530)	(14,125)	(277,508)
Premiums Earned, Net, Financial Guarantee Insurance Contracts										29,744	100,256	130,000	414,604
Net Investment Income										32,226	84,514	116,740	382,902
Net Other Than Temporary Impairment Losses Recognized In Earnings										(467)	0
Net realized investment gains										7,245	46,060	53,305	72,101
Gain (Loss) on Derivative Instruments, Net, Pretax										(73,171)	12,787	(60,384)	(9,219)
Gain (Loss) on Derivative Instruments Held for Trading Purposes, Net										(33,166)	(569)	(33,735)	(125,004)
Net realized losses on extinguishment of debt												0	(177,580)
Variable Interest Entity, Measure of Activity, Operating Income or Loss										388,240	38,326	426,566	27,777
Policyholder Benefits and Claims Incurred, Net, Financial Guarantee										13,079	(51,135)	(38,056)	683,630
Amortization of insurance intangible assets										0	0	0	0
Other Underwriting Expense										10,692	33,874	44,566	139,029
Interest Expense, Debt										7,860	23,165	31,025	112,320
Reorganization items										(2,747,239)	2,059	(2,745,180)	7,215
Pre-tax (loss) income from continuing operations										3,065,124	282,909	3,348,033	(256,505)
Net Income (Loss) Attributable to Parent										$ 3,066,750	$ 282,299	$ 3,349,049	$ (256,678)
Earnings Per Share, Basic										$ 10.14	$ 0.93	$ 11.07	$ (0.85)
Earnings Per Share, Diluted										$ 10.14	$ 0.93	$ 11.07	$ (0.85)