Derivative Instruments - Narrative (Detail) - USD ($)			12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Realized gains (losses) on terminations of interest rate swaps			$ (359,726,000)	$ 0	$ (16,143,000)
The weighted average pay rate on the Company's interest rate swaps	2.62%	2.58%	2.62%	2.58%
The weighted average receive rate on the Company's interest rate swaps	1.94%	2.69%	1.94%	2.69%
The weighted average maturity on the Company's interest rate swaps	6 years	7 years
Fair value of credit risk derivative instruments in a net asset (liability) position	$ (215,000,000)		$ (215,000,000)
Interest Rate Swaps
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount of derivative terminated			$ 6,400,000,000