Fair Value Measurements - Summary of Information about Described Model Inputs Used to Determine Fair Value of Each Class of Credit Derivatives (Detail) - Underlying Asset Class [Domain] - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative, Notional Amount	$ 1,447,939	$ 1,529,759
Successor [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative, Notional Amount	1,447,939	1,529,759
Successor [Member] | CLO [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative, Notional Amount	$ 433,555	$ 549,923
Weighted average reference obligation price	$ 99.0	$ 98.9
Weighted average life (WAL) in years	1 year 3 months	1 year 9 months
Weighted average credit rating	AA	AA
Weighted average relative change ratio	36.20%	35.90%
CVA percentage	8.20%	5.40%
Fair value of derivative liabilities	$ 1,518	$ 2,027
Successor [Member] | Other [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative, Notional Amount	$ 955,902	$ 921,036
Weighted average reference obligation price	$ 85.3	$ 86.8
Weighted average life (WAL) in years	6 years 3 months	5 years 8 months
Weighted average credit rating	BBB-	BBB-
Weighted average relative change ratio	45.00%	49.00%
CVA percentage	28.12%	15.82%
Fair value of derivative liabilities	$ 64,936	$ 71,104