Financial Guarantee Insurance Contracts - Effect of Reinsurance on Premiums Written and Earned (Detail) - Successor [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct Premiums Written	$ (24,696)	$ (10,543)	$ (12,184)	$ (39,364)
Assumed Reinsurance Premiums Written	0	0	0	0
Ceded Reinsurance Premiums Written	(385)	(1,526)	(1,962)	(8,425)
Premiums written, net of reinsurance	24,311	9,017	10,222	30,939
Direct Premiums Earned	57,282	59,096	156,582	161,058
Assumed Reinsurance Premiums Earned	20	21	61	64
Ceded Reinsurance Premiums Earned	4,313	5,899	12,889	13,702
Reinsurance on premiums earned, Net	$ 52,989	$ 53,218	$ 143,754	$ 147,420