Equity and Regulatory Matters - Schedule of Banks Actual and Required Capital Amounts and Ratios (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Banking and Thrift [Abstract]
Leverage tier 1 capital actual amount	$ 46,634	$ 46,316
Common Equity Tier 1 risk based capital actual amount	46,634	46,316
Tier 1 risk based capital actual amount	46,634	46,316
Total risk based capital actual amount	$ 48,642	$ 48,316
Leverage tier 1 capital actual ratio	10.90%	10.70%
Common Equity Tier 1 risk based capital actual ratio	13.80%	13.50%
Tier 1 risk based capital actual ratio	13.80%	13.50%
Total risk based capital actual ratio	14.40%	14.10%
Leverage tier 1 capital for capital adequacy purposes amount	$ 17,147	$ 17,392
Common Equity Tier 1 risk based capital for capital adequacy purposes amount	15,206	15,391
Tier 1 risk based capital for capital adequacy purposes amount	20,275	20,522
Total risk based capital for capital adequacy purposes amount	$ 27,033	$ 27,362
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	4.50%	4.50%
Tier 1 risk based capital for capital adequacy purposes ratio	6.00%	6.00%
Total risk based capital for capital adequacy purposes ratio	8.00%	8.00%
Leverage tier 1 capital to be well capitalized under prompt corrective action provisions amount	$ 21,434	$ 21,740
Common Equity Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	21,964	22,232
Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	27,033	27,362
Total risk based capital to be well capitalized under prompt corrective action provisions amount	$ 33,791	$ 34,203
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	6.50%	6.50%
Tier 1 risk based capital to be well capitalized under prompt corrective action provisions ratio	8.00%	8.00%
Total risk based capital to be well capitalized under prompt corrective action provisions ratio	10.00%	10.00%

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

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The minimum Common Tier One Capital Ratio (Common Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of total capital as defined in the regulations.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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