Segment Information - Schedule of Gross Premiums Written, Net Premiums Earned and Net Change in Fair Value of Credit Derivatives (Detail) - Successor [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Gross Premiums Written	$ (11,192)	$ (45,486)	$ (10,130)	$ (51,252)
Net premiums earned	60,879	65,013	126,597	147,560
Net Change In Fair Value Of Credit Derivatives	10,293	(1,219)	7,794	6,163
Reportable Geographical Components [Member] | United States [Member]
Segment Reporting Information [Line Items]
Gross Premiums Written	(547)	(28,211)	(2,913)	(28,909)
Net premiums earned	49,710	39,833	102,448	96,591
Net Change In Fair Value Of Credit Derivatives	4,724	(559)	8,681	6,022
Reportable Geographical Components [Member] | United Kingdom [Member]
Segment Reporting Information [Line Items]
Gross Premiums Written	(2,139)	3,003	7,035	(3,163)
Net premiums earned	7,997	20,808	15,579	41,443
Net Change In Fair Value Of Credit Derivatives	0	0	0	0
Reportable Geographical Components [Member] | Other International [Member]
Segment Reporting Information [Line Items]
Gross Premiums Written	(8,506)	(20,278)	(14,252)	(19,180)
Net premiums earned	3,172	4,372	8,570	9,526
Net Change In Fair Value Of Credit Derivatives	$ 5,569	$ (660)	$ (887)	$ 141