Investment Securities - Narrative (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($) Investment	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($) Investment	Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items]
Carrying value of securities pledged to secure public deposits and other contractual obligations	$ 439,900		$ 281,700
Pledging requirements for credit derivatives and SWAP agreements - securities		$ 0	$ 23,000
Number of investments in non federal issuer representing more than 10% of shareholder's equity | Investment	0		0
Maximum investment in any single non-federal issuer representing shareholders equity	10.00%		10.00%
Fair value HTM in unrealized loss with no ACL	$ 133,809		$ 89,837
Unrealized loss included in fair value of securities HTM in unrealized loss position for which an ACL has not been recorded	8,698		984
Fair value AFS in unrealized loss with no ACL	259,876		179,992
Unrealized loss included in fair value of securities AFS in unrealized loss position for which an ACL has not been recorded	19,224		2,300
Fair value of securities AFS in unrealized loss position for which an ACL has been recorded, net of allowance	74,100
Unrealized loss position included in fair value of securities AFS in unrealized loss position for which an ACL has been recorded	3,700
Debt securities, available-for-sale, allowance for credit loss	(1,275)		(929)
Corporate Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Fair value AFS in unrealized loss with no ACL	1,280		779
Unrealized loss included in fair value of securities AFS in unrealized loss position for which an ACL has not been recorded	1		1
Debt securities, available-for-sale, allowance for credit loss	$ (1,275)	(485)	$ (929)	$ (869)
Number of securities | Investment	33
Available-for-sale Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivable	$ 821
Debt securities, available-for-sale, allowance for credit loss	(1,300)
Held-to-maturity Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivable	351
Other Noninterest Income [Member] | Equity Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Net realized gain on investment securities	$ 1	$ 115