Interest Rate Swap Derivatives - Summary Information about the Interest Rate Swap Derivative Instruments (Detail) - Interest Rate Swap [Member] - Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Notional amount	$ 12,408,888	$ 10,596,427
Weighted average pay rate on interest-rate swaps	2.70%	3.20%
Weighted average receive rate on interest rate swaps	2.70%	3.20%
Weighted average maturity (years)	11 years	11 years
Fair value of interest rate swap derivatives (asset)	$ 831,891	$ 273,068
Fair value of interest rate swap derivatives (liability)	$ 833,977	$ 274,216