Derivative Instruments - Summary of Notional for VIE Derivatives Outstanding (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items]
Derivative products, Notional Amount	$ 737,380	$ 970,883
Successor [Member]
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items]
Derivative products, Notional Amount	737,380	970,883
Variable Interest Entity, Primary Beneficiary [Member] | Successor [Member] | Interest Rate Swaps [Member]
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items]
Derivative products, Notional Amount	1,352,010	1,616,289
Variable Interest Entity, Primary Beneficiary [Member] | Successor [Member] | Interest Rate Swaps-Pay-Fixed/Receive-Variable [Member]
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items]
Derivative products, Notional Amount	2,300,584	2,796,496
Variable Interest Entity, Primary Beneficiary [Member] | Successor [Member] | Currency Swaps [Member]
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items]
Derivative products, Notional Amount	312,357	331,992
Variable Interest Entity, Primary Beneficiary [Member] | Successor [Member] | Credit Derivatives [Member]
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items]
Derivative products, Notional Amount	$ 12,059	$ 15,616