Quarterly Information (unaudited) Quarterly Information (unaudited) (Details) - Successor [Member] - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Gross Premiums Written	$ 14,473	$ 10,543	$ (4,041)	$ (24,780)	$ (18,732)	$ (8,710)	$ (11,192)	$ (1,062)	$ (53,837)	$ (37,572)	$ 288,310
Premiums Earned, Net, Financial Guarantee Insurance Contracts	49,867	53,218	41,402	52,800	114,463	71,535	60,879	65,718	197,287	312,595	246,360
Net Investment Income	90,871	90,917	70,758	60,821	64,358	64,195	64,753	72,983	313,367	266,289	300,946
Net Other Than Temporary Impairment Losses Recognized In Earnings	(2,191)	(2,853)	(7,441)	(9,334)	(12,370)	(9,150)	(1,020)	(3,119)
Net realized investment gains	11,536	11,749	14,897	1,102	2,622	2,106	(5,353)	54,101	39,284	53,476	58,777
Gain (Loss) on Derivative Instruments, Net, Pretax	1,552	1,733	3,955	12,866	(3,045)	36,952	10,293	(2,499)	20,106	41,701	23,906
Gain (Loss) on Derivative Instruments Held for Trading Purposes, Net	83,992	(14,510)	(36,331)	(83,424)	9,314	(65,083)	50,999	(37,774)	(50,273)	(42,544)	(181,087)
Net realized gains (losses) on extinguishment of debt	0	24	3,586	1,235	0	1,420	(1,246)	(93)	4,845	81	(74,724)
Variable Interest Entity, Measure of Activity, Operating Income or Loss	2,026	2,057	8,987	(27,163)	(6,561)	(21,435)	52,603	6,962	(14,093)	31,569	(32,212)
Policyholder Benefits and Claims Incurred, Net, Financial Guarantee	215,492	(69,204)	(52,496)	(105,281)	(337,065)	(133,213)	(147,477)	(150,952)	(11,489)	(768,707)	(545,574)
Amortization of insurance intangible assets	40,152	44,553	39,013	50,890	54,357	39,680	38,088	37,432	174,608	169,557	151,830
Other Underwriting Expense	36,190	21,466	27,995	28,009	27,300	25,006	25,873	24,523	113,660	102,702	101,474
Interest Expense, Debt	31,712	31,493	30,709	30,430	30,557	29,899	28,173	27,908	124,344	116,537	127,476
Goodwill, Impairment Loss	0	0	0	0	0	(514,511)	0	0	0	514,511	0
Reorganization items									0	0	211
Pre-tax (loss) income from continuing operations	(86,059)	116,720	61,511	12,854	395,576	(388,193)	286,095	216,580	105,026	510,058	493,253
Net Income (Loss) Attributable to Parent	$ (94,693)	$ 101,474	$ 58,647	$ 9,415	$ 386,984	$ (390,987)	$ 282,695	$ 214,711	$ 74,843	$ 493,403	$ 484,071
Earnings Per Share, Basic	$ (2.09)	$ 2.24	$ 1.30	$ 0.21	$ 8.57	$ (8.66)	$ 6.26	$ 4.75	$ 1.66	$ 10.92	$ 10.73
Earnings Per Share, Diluted	$ (2.09)	$ 2.22	$ 1.29	$ 0.21	$ 8.56	$ (8.66)	$ 6.05	$ 4.57	$ 1.64	$ 10.72	$ 10.31