Equity and Regulatory Matters - Schedule of Banks Actual and Required Capital Amounts and Ratios (Detail) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Text Block [Abstract]
Leverage tier 1 capital actual amount	$ 65,179	$ 49,534
Common Equity Tier 1 risk based capital actual amount	65,179	49,534
Tier 1 risk based capital actual amount	65,179	49,534
Total risk based capital actual amount	$ 68,037	$ 52,237
Leverage tier 1 capital actual ratio	0.119	0.098
Common Equity Tier 1 risk based capital actual ratio	0.194	0.151
Tier 1 risk based capital actual ratio	0.194	0.151
Total risk based capital actual ratio	0.202	0.160
Leverage tier 1 capital for capital adequacy purposes amount	$ 21,838	$ 20,195
Common Equity Tier 1 risk based capital for capital adequacy purposes amount	15,124	14,725
Tier 1 risk based capital for capital adequacy purposes amount	20,166	19,633
Total risk based capital for capital adequacy purposes amount	$ 26,888	$ 26,177
Leverage tier 1 capital for capital adequacy purposes ratio	4.00%	4.00%
Common Equity Tier 1 risk based capital for capital adequacy purposes ratio	0.045	0.045
Tier 1 risk based capital for capital adequacy purposes ratio	0.060	0.060
Total risk based capital for capital adequacy purposes ratio	0.080	0.080
Leverage tier 1 capital to be well capitalized under prompt corrective action provisions amount	$ 27,298	$ 25,243
Common Equity Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	21,846	21,269
Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	26,888	26,177
Total risk based capital to be well capitalized under prompt corrective action provisions amount	$ 33,610	$ 32,722
Leverage tier 1 capital to be well capitalized under prompt corrective action provisions ratio	5.00%	5.00%
Common Equity Tier 1 risk based capital to be well capitalized under prompt corrective action provisions ratio	0.065	0.065
Tier 1 risk based capital to be well capitalized under prompt corrective action provisions ratio	0.080	0.080
Total risk based capital to be well capitalized under prompt corrective action provisions ratio	0.100	0.100

Common Equity Tier One Capital Required To Be Well Capitalized To Risk Weighted Assets

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Common Equity Tier One Risk Based Capital Required For Capital Adequacy

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Amount of total capital as defined by regulatory framework.

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