Securities - Schedule of Other Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Other Securities [Line Items]
Other securities	$ 327,098	$ 296,053
FRB and FHLB stock [Member]
Schedule of Other Securities [Line Items]
Other securities	36,222	33,222
Equity Securities With Readily Determinable Fair Values [Member]
Schedule of Other Securities [Line Items]
Other securities	64,149	134,197
Equity Securities Without Readily Determinable Fair Values [Member]
Schedule of Other Securities [Line Items]
Other securities	$ 226,727	$ 128,634