Financial Guarantee Insurance Contracts - Estimated Future Amortization Expense for Insurance Intangible Asset (Detail) - Successor [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Amortization Of Intangible Assets [Line Items]
Amortization of insurance intangible assets	$ 33,471	$ 39,013	$ 70,996	$ 89,903
Intangible Assets, Gross (Excluding Goodwill)	1,561,592		1,561,592		$ 1,534,419
Accumulated amortization on insurance intangible asset	649,419		649,419		572,339
2016	45,673		45,673
2017	80,743		80,743
2018	72,291		72,291
2019	66,509		66,509
2020	60,041		60,041
Thereafter	586,916		586,916
Insurance intangible asset	$ 912,173		$ 912,173		$ 962,080