Derivatives and Hedging Activities - Summary of Amount of Gain (Loss) Recognized in Interest Income and Other Non-interest Expense in Consolidated Statements of Income Related to Derivative Assets and Liabilities (Detail) - Interest Rate Swap [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Derivatives not Designated as Hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized	$ 489	$ (259)
Derivatives Designated as Hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized	77	(1)
Derivatives Designated as Hedging Instruments [Member] | Fair value adjustments on derivatives [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized	9,328	(203)
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized	$ (9,251)	$ 202