Financial Guarantee Insurance Contracts - Estimated Future Amortization Expense for Insurance Intangible Asset (Detail) - USD ($) $ in Thousands	3 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	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Insurance Intangible Asset [Member]
Amortization Of Intangible Assets [Line Items]
2015	$ 111,857									$ 111,857
2016	98,570									98,570
2017	88,388									88,388
2018	81,370									81,370
2019	75,743									75,743
Thereafter	756,184									756,184
Successor [Member]
Amortization Of Intangible Assets [Line Items]
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
Intangible Assets, Gross (Excluding Goodwill)	1,626,566				1,660,125					1,626,566	1,660,125
Accumulated amortization on insurance intangible asset	$ 414,454				$ 249,205					414,454	249,205
Successor [Member] | Insurance Asset [Member]
Amortization Of Intangible Assets [Line Items]
Amortization of insurance intangible assets										$ 169,557	$ 151,830	$ 99,658