Loans and Allowance for Credit Losses - Troubled Debt Restructured Loans and Commitments (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure [Abstract]
Accrual status	$ 6,442	$ 7,120	$ 8,512
Nonaccrual status	8,852	13,134	14,740
Total	15,294	20,254	23,252
Letters of Credit Outstanding, Amount	60	60	60
Unused lines of credit	23	16	11
Commitments Net	$ 83	$ 76	$ 71