Derivative Instruments - Summarize Information by Major Category of CDS Contracts (Detail) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2016 USD ($) Transactions	Dec. 31, 2015 USD ($) Transactions
Summary of information by major category of CDS contracts
Gross principal notional outstanding	$ 861,511	$ 970,883
Successor [Member]
Summary of information by major category of CDS contracts
Number of CDS transactions | Transactions	9	14
Derivative, Average Remaining Maturity	4 years 11 months	4 years 3 months
Gross principal notional outstanding	$ 861,511	$ 970,883
Successor [Member] | Credit Derivatives [Member]
Summary of information by major category of CDS contracts
Net derivative liabilities at fair value	$ 18,207	$ 34,543
CLO [Member] | Successor [Member]
Summary of information by major category of CDS contracts
Number of CDS transactions | Transactions	4	5
Derivative, Average Remaining Maturity	11 months	1 year 1 month
Gross principal notional outstanding	$ 231,376	$ 295,254
CLO [Member] | Successor [Member] | Credit Derivatives [Member]
Summary of information by major category of CDS contracts
Net derivative liabilities at fair value	$ 878	$ 1,837
Other [Member] | Successor [Member]
Summary of information by major category of CDS contracts
Number of CDS transactions | Transactions	5	9
Derivative, Average Remaining Maturity	6 years 5 months	5 years 7 months
Gross principal notional outstanding	$ 630,135	$ 675,629
Other [Member] | Successor [Member] | Credit Derivatives [Member]
Summary of information by major category of CDS contracts
Net derivative liabilities at fair value	$ 17,329	$ 32,706