Financial Guarantee Insurance Contracts - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Insurance [Line Items]
Estimated Future Premium Payments Weighted Average Discounted Rate	2.70%		2.70%
Losses and loss expense reserves ceded to reinsurers	$ 71,031		$ 71,031
Successor [Member]
Insurance [Line Items]
Estimated Future Premium Payments Weighted Average Discounted Rate					2.70%
Reinsurance Payable	58,002		$ 58,002		$ 60,436
Weighted average period of future premiums			9 years 6 months		10 years 1 month 6 days
Transactions with non-investment grade internal ratings			27.00%		32.00%
Non-investment grade RMBS on total premiums receivable			8.00%		7.00%
Percentage of Premiums Receivable Related To Non Investment Grade Lease Securitizations			6.00%		6.00%
Percentage of student loan transactions on total premium receivables			5.00%		8.00%
Uncollectable premium receivables	14,973		$ 14,973		$ 17,780
Past due premiums on policies insuring non-investment grade obligations amount			500
Accelerated premium revenue for retired obligations	13,641	$ 7,990	36,493	$ 33,104
Reinsurance recoveries of losses included in losses and loss expenses	3,219	1,602	23,821	12,160
Losses and loss expense reserves ceded to reinsurers	71,031	110,015	71,031	110,015	100,355	$ 122,357
Subrogation recoveries	2,556,574		2,556,574		2,523,540
Subrogation recoveries, net of reinsurance	2,529,300		2,529,300		2,496,515
Intangible amortization expense	38,088	$ 36,256	75,520	$ 67,970
Insurance intangible asset	1,339,427		1,339,427		1,410,920
Accumulated amortization on insurance intangible asset	$ 325,660		$ 325,660		$ 249,205
Loss Reserves [Member] | Successor [Member]
Insurance [Line Items]
Weighted average risk-free rate used to discount loss reserves			2.50%		2.30%