Derivatives and Hedging Activities - Summary of Effect of Hedges on AOCI in Consolidated Statements of Comprehensive Income Related to Company's Derivative Assets and Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Change in unrealized gains and losses on derivative hedges	$ 4,612	$ (3,061)	$ 19,137	$ (5,149)
Gain (Loss) Reclassified from AOCI into Earnings	514	(20)	(254)	(15)
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in unrealized gains and losses on derivative hedges	4,612	(3,061)	19,137	(5,149)
Gain (Loss) Recognized in OCI Included Component	6,122	(3,061)	25,009	(5,149)
Loss Recognized in OCI Excluded Component	(1,510)		(5,872)
Gain (Loss) Reclassified from AOCI into Earnings	514	(20)	(254)	(15)
Gain (Loss) Reclassified from AOCI into Earnings Included Component	1,150	(20)	1,018	(15)
Loss Reclassified from AOCI into Earnings Excluded Component	(636)		(1,272)
Derivatives Designated as Hedging Instruments [Member] | Interest Rate Floor [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in unrealized gains and losses on derivative hedges	4,687		29,621
Gain (Loss) Recognized in OCI Included Component	6,197		35,493
Loss Recognized in OCI Excluded Component	(1,510)		(5,872)
Gain (Loss) Reclassified from AOCI into Earnings	771		135
Gain (Loss) Reclassified from AOCI into Earnings Included Component	1,407		1,407
Loss Reclassified from AOCI into Earnings Excluded Component	(636)		(1,272)
Derivatives Designated as Hedging Instruments [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in unrealized gains and losses on derivative hedges	(75)	(3,061)	(10,484)	(5,149)
Gain (Loss) Recognized in OCI Included Component	(75)	(3,061)	(10,484)	(5,149)
Gain (Loss) Reclassified from AOCI into Earnings	(257)	(20)	(389)	(15)
Gain (Loss) Reclassified from AOCI into Earnings Included Component	$ (257)	$ (20)	$ (389)	$ (15)