Fair Value Measurements - Summary of Gains and Losses (Realized and Unrealized) Relating to Level 3 Assets and Liabilities Included in Earnings (Detail) - Successor [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Variable Interest Entity [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total gains or losses included in earnings for the period	$ 833,023	$ (590,327)	$ 1,256,740
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held	833,023	(579,620)	1,261,927
Net Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total gains or losses included in earnings for the period	54,600	30,083	11,057
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held	0	0	0
Realized Gains Or (Losses) and Other Settlements On Credit Derivative Contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total gains or losses included in earnings for the period	912	2,785	3,043
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held	0	0	0
Unrealized Gains Or Losses On Credit Derivative Contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total gains or losses included in earnings for the period	19,194	38,916	20,863
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held	19,129	(850)	15,789
Interest Rate Swaps [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total gains or losses included in earnings for the period	(35,480)	(25,130)	(69,298)
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held	(35,480)	(25,130)	(69,298)
Other Income or (Loss) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total gains or losses included in earnings for the period	(1,314)	(1,635)	(1,348)
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held	$ (1,314)	$ (1,635)	$ (1,348)