Equity and Regulatory Matters - Schedule of Banks Actual and Required Capital Amounts and Ratios (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Banking and Thrift [Abstract]
Leverage tier 1 capital actual amount	$ 45,597	$ 35,955
Common Equity Tier 1 risk based capital actual amount	45,597	35,955
Tier 1 risk based capital actual amount	45,597	35,955
Total risk based capital actual amount	$ 48,615	$ 39,217
Leverage tier 1 capital actual ratio	9.90%	7.50%
Common Equity Tier 1 risk based capital actual ratio	13.10%	10.00%
Tier 1 risk based capital actual ratio	13.10%	10.00%
Total risk based capital actual ratio	13.90%	10.90%
Leverage tier 1 capital for capital adequacy purposes amount	$ 18,367	$ 19,110
Common Equity Tier 1 risk based capital for capital adequacy purposes amount	15,702	16,153
Tier 1 risk based capital for capital adequacy purposes amount	20,936	21,538
Total risk based capital for capital adequacy purposes amount	$ 27,915	$ 28,717
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	$ 22,959	$ 23,887
Common Equity Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	22,681	23,333
Tier 1 risk based capital to be well capitalized under prompt corrective action provisions amount	27,915	28,717
Total risk based capital to be well capitalized under prompt corrective action provisions amount	$ 34,894	$ 35,897
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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Common Equity Tier One Risk Based Capital Required For Capital Adequacy

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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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Amount of Common Equity Tier One Risk-based Capital, as defined by regulatory framework.

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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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