Comprehensive Income - Components of Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Before Tax Amount
Other comprehensive loss, net	$ (42,140)	$ (18,570)
Tax Benefit (Expense)
Other comprehensive loss, net	11,040	5,482
Net of Tax Amount
Other comprehensive loss, net of tax	(31,100)	(13,088)
Net unrealized holding losses arising during period
Before Tax Amount
Net unrealized holding losses arising during period	(41,964)	(18,637)
Tax Benefit (Expense)
Net unrealized holding losses arising during period	10,999	5,502
Net of Tax Amount
Net current period other comprehensive income	(30,965)	(13,135)
Amortization of Gain on Debt Securities Reclassified to Held to Maturity
Before Tax Amount
Other comprehensive loss, net	(176)	0
Tax Benefit (Expense)
Other comprehensive loss, net	41	0
Net of Tax Amount
Other comprehensive loss, net of tax	(135)	0
Unrealized gains on derivatives
Before Tax Amount
Other comprehensive loss, net	0	67
Tax Benefit (Expense)
Other comprehensive loss, net	0	(20)
Net of Tax Amount
Other comprehensive loss, net of tax	$ 0	$ 47