Comprehensive Income - Components of Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Before Tax Amount
Other comprehensive (loss) gains, net	$ (26,961)	$ 9,797	$ (69,101)	$ (8,773)
Tax Benefit (Expense)
Other comprehensive (loss) gains, net	7,125	(2,761)	18,165	2,721
Net of Tax Amount
Net current period other comprehensive loss		7,042		(6,046)
Amounts reclassified from accumulated other comprehensive income		(6)		(6)
Other comprehensive loss, net of tax	(19,836)	7,036	(50,936)	(6,052)
Unrealized (losses) gains on available for sale securities arising during the period:
Before Tax Amount
Unrealized (losses) gains on available for sale securities arising during the period:	26,758	(9,738)	68,722	8,899
Tax Benefit (Expense)
Unrealized (losses) gains on available for sale securities arising during the period:	7,070	(2,619)	18,069	2,883
Net of Tax Amount
Net current period other comprehensive loss	(19,688)	7,119	(50,653)	(6,016)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Before Tax Amount
Reclassification adjustment for securities gains arising during the period	0	9	0	9
Other comprehensive (loss) gains, net	(26,758)	9,729	(68,722)	(8,908)
Tax Benefit (Expense)
Reclassification adjustment for securities gains arising during the period	0	3	0	3
Other comprehensive (loss) gains, net	7,070	(2,616)	18,069	2,886
Net of Tax Amount
Net current period other comprehensive loss		7,119		(6,016)
Amounts reclassified from accumulated other comprehensive income	0	(6)	0	(6)
Other comprehensive loss, net of tax	(19,688)	7,113	(50,653)	(6,022)
Amortization of Gain on Debt Securities Reclassified to Held to Maturity
Before Tax Amount
Other comprehensive (loss) gains, net	(203)	0	(379)	0
Tax Benefit (Expense)
Other comprehensive (loss) gains, net	55	0	96	0
Net of Tax Amount
Other comprehensive loss, net of tax	(148)	0	(283)	0
Unrealized gains on derivatives
Before Tax Amount
Other comprehensive (loss) gains, net	0	68	0	135
Tax Benefit (Expense)
Other comprehensive (loss) gains, net	0	(145)	0	(165)
Net of Tax Amount
Net current period other comprehensive loss		(77)		(30)
Amounts reclassified from accumulated other comprehensive income		0		0
Other comprehensive loss, net of tax	$ 0	$ (77)	$ 0	$ (30)