Segment Information - Summary of Financial Information by Reportable Segment (Detail) - USD ($) $ 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
Pre-tax income (loss) from continuing operations:
Total assets									$ 28,853,435
Goodwill, Impairment Loss		$ 514,511
Successor [Member]
Revenues:
Total revenues before expenses and reorganization items										$ 581,048	$ 644,658	$ 328,670
Pre-tax income (loss) from continuing operations:
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
Total assets	23,728,070				25,159,864				28,853,435	27,092,477	23,728,070	25,159,864
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
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
Interest expense	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
Successor [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items										581,048	640,322	327,275
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										512,316	505,722	491,858
Successor [Member] | Equity Method Investee [Member]
Revenues:
Total revenues before expenses and reorganization items											4,336	1,395
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations											4,336	1,395
Successor [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items										0	0	0
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										0	0	0
Successor [Member] | Financial Guarantee [Member]
Revenues:
Total revenues before expenses and reorganization items										466,538	680,011	507,802
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										184,786	557,588	659,307
Total assets	23,108,387				24,448,346					26,590,873	23,108,387	24,448,346
Net investment income										145,269	256,636	298,020
Amortization of insurance intangible assets										99,658	169,557	151,830
Interest expense										83,595	115,630	125,892
Goodwill, Impairment Loss											514,511
Reorganization items										0	0	0
Successor [Member] | Financial Guarantee [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items										464,701	679,662	506,559
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										405,004	560,332	684,750
Successor [Member] | Financial Guarantee [Member] | Equity Method Investee [Member]
Revenues:
Total revenues before expenses and reorganization items											0	0
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations											0	0
Successor [Member] | Financial Guarantee [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items										1,837	349	1,243
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										(220,218)	(2,744)	(25,443)
Successor [Member] | Financial Services [Member]
Revenues:
Total revenues before expenses and reorganization items										114,967	(44,852)	(180,888)
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										111,703	(48,252)	(184,486)
Total assets	348,130				412,510					448,473	348,130	412,510
Net investment income										1,115	548	1,123
Interest expense										1,355	907	1,584
Goodwill, Impairment Loss											0
Reorganization items										0	0	0
Successor [Member] | Financial Services [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items										116,177	(44,003)	(179,691)
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										113,347	(46,869)	(182,941)
Successor [Member] | Financial Services [Member] | Equity Method Investee [Member]
Revenues:
Total revenues before expenses and reorganization items											0	0
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations											0	0
Successor [Member] | Financial Services [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items										(1,210)	(849)	(1,197)
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										(1,644)	(1,383)	(1,545)
Successor [Member] | Corporate and Other [Member]
Revenues:
Total revenues before expenses and reorganization items										219,351	9,644	25,101
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										215,827	722	18,432
Total assets	268,388				284,278					53,908	268,388	284,278
Net investment income										62	9,105	1,803
Interest expense										0	0	0
Goodwill, Impairment Loss											0
Reorganization items										493	0	211
Successor [Member] | Corporate and Other [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items										170	4,663	407
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										(6,035)	(7,741)	(9,951)
Successor [Member] | Corporate and Other [Member] | Equity Method Investee [Member]
Revenues:
Total revenues before expenses and reorganization items											4,336	1,395
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations											4,336	1,395
Successor [Member] | Corporate and Other [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items										219,181	645	23,299
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										221,862	4,127	26,988
Predecessor [Member]
Revenues:
Total revenues before expenses and reorganization items									640,388
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									3,348,033
Total assets									28,853,435
Net investment income									116,740
Amortization of insurance intangible assets									0
Interest expense									31,025
Reorganization items									(2,745,180)
Predecessor [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items									640,388
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									3,348,033
Predecessor [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items									0
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									0
Predecessor [Member] | Financial Guarantee [Member]
Revenues:
Total revenues before expenses and reorganization items									633,950
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									1,831,105
Total assets									28,302,214
Net investment income									115,129
Interest expense									29,718
Reorganization items									(1,231,550)
Predecessor [Member] | Financial Guarantee [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items									633,010
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									1,831,237
Predecessor [Member] | Financial Guarantee [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items									940
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									(132)
Predecessor [Member] | Financial Services [Member]
Revenues:
Total revenues before expenses and reorganization items									6,457
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									2,293
Total assets									512,021
Net investment income									1,572
Interest expense									1,307
Reorganization items									1,505
Predecessor [Member] | Financial Services [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items									7,339
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									3,394
Predecessor [Member] | Financial Services [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items									(882)
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									(1,101)
Predecessor [Member] | Corporate and Other [Member]
Revenues:
Total revenues before expenses and reorganization items									39
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									1,514,635
Total assets									31,070
Net investment income									39
Interest expense									0
Reorganization items									(1,515,135)
Predecessor [Member] | Corporate and Other [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items									39
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									1,513,402
Predecessor [Member] | Corporate and Other [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items									0
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									1,233
Inter-segment Eliminations [Member] | Successor [Member]
Revenues:
Total revenues before expenses and reorganization items										(219,808)
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										0
Total assets										(777)
Net investment income										0
Interest expense										0
Reorganization items										0
Inter-segment Eliminations [Member] | Successor [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items										0
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										0
Inter-segment Eliminations [Member] | Successor [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items										(219,808)	(145)	(23,345)
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations										$ 0
Inter-segment Eliminations [Member] | Successor [Member] | Inter-segment Eliminations [Member]
Revenues:
Total revenues before expenses and reorganization items											(145)	(23,345)
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations											0	0
Total assets	$ 3,165				$ 14,730						3,165	14,730
Net investment income											0	0
Interest expense											0	0
Goodwill, Impairment Loss											0
Reorganization items											0	0
Inter-segment Eliminations [Member] | Successor [Member] | Inter-segment Eliminations [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items											0	0
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations											0	0
Inter-segment Eliminations [Member] | Successor [Member] | Inter-segment Eliminations [Member] | Equity Method Investee [Member]
Revenues:
Total revenues before expenses and reorganization items											0	0
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations											0	0
Inter-segment Eliminations [Member] | Successor [Member] | Inter-segment Eliminations [Member] | Intersegment [Member]
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations											$ 0	$ 0
Inter-segment Eliminations [Member] | Predecessor [Member]
Revenues:
Total revenues before expenses and reorganization items									(58)
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									0
Total assets									8,130
Net investment income									0
Interest expense									0
Reorganization items									0
Inter-segment Eliminations [Member] | Predecessor [Member] | Unaffiliated Customers [Member]
Revenues:
Total revenues before expenses and reorganization items									0
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									0
Inter-segment Eliminations [Member] | Predecessor [Member] | Intersegment [Member]
Revenues:
Total revenues before expenses and reorganization items									(58)
Pre-tax income (loss) from continuing operations:
Pre-tax (loss) income from continuing operations									$ 0