Regulatory Capital Requirements - Schedule of Bank Actual and Required Capital Amounts and Ratios (Detail) $ in Thousands	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Total capital
Actual	$ 277,027	$ 251,042
For capital adequacy purposes	193,699	188,807
To be well capitalized	242,124	236,009
Tier 1 capital
Actual	257,229	234,533
For capital adequacy purposes	145,274	141,605
To be well capitalized	193,699	188,807
Common equity
Actual	257,229	234,533
For capital adequacy purposes	108,956	106,204
To be well capitalized	157,381	153,406
Tier 1 capital
Actual	257,229	234,533
For capital adequacy purposes	109,387	66,412
To be well capitalized	$ 136,734	$ 83,016
Ratios
Actual	0.1144	0.1062
For capital adequacy purposes	0.08	0.08
To be well capitalized	0.10	0.10
Actual	0.1062	0.0992
For capital adequacy purposes	0.06	0.06
To be well capitalized	0.08	0.08
Actual	0.1062	0.0992
For capital adequacy purposes	0.045	0.045
To be well capitalized	0.065	0.065
Banking Regulation, Leverage Ratio [Abstract]
Actual	0.0941	0.1413
For capital adequacy purposes	0.04	0.04
To be well capitalized	0.05	0.05