Financial Guarantee Insurance Contracts - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended	3 Months Ended		3 Months Ended			3 Months Ended		12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Successor Ambac [Member]	Dec. 31, 2013 Successor Ambac [Member]	Mar. 31, 2014 Successor Ambac [Member] Insurance Intangible Asset [Member]	Mar. 31, 2013 Predecessor Ambac [Member]	Dec. 31, 2012 Predecessor Ambac [Member]	Mar. 31, 2014 Maximum [Member]	Mar. 31, 2014 Loss Reserves [Member]	Dec. 31, 2013 Loss Reserves [Member]
Insurance [Line Items]
Weighted average risk-free interest rate	2.90%	3.00%
Weighted average period of future premiums	9 years 8 months 12 days	9 years 7 months 6 days
Transactions with non-investment grade internal ratings	45.00%	44.00%
Non-investment grade RMBS on total premiums receivable	6.00%	7.00%
Percentage of student loan transactions on total premium receivables	7.00%	7.00%
Percentage related to asset-backed transaction	17.00%	17.00%
Uncollectable premium receivables			$ 16,336	$ 15,262
Past due premiums on policies insuring non-investment grade obligations amount								500
Accelerated premium revenue for retired obligations			25,114			29,360
Reinsurance recoveries of losses included in losses and loss expenses			(10,559)			3,881
Weighted average risk-free rate used to discount loss reserves									2.90%	3.20%
Losses and loss expense reserves ceded to reinsurers			111,303	122,357		148,749	147,409
Subrogation recoveries	2,224,295	2,206,598
Subrogation recoveries, net of reinsurance	2,201,983	2,183,652
Intangible amortization expense			31,714		31,714	0
Insurance intangible asset	1,570,070	1,597,965
Accumulated amortization on insurance intangible asset	$ 132,688	$ 100,767