Note 14 - Regulatory Matters - Summary of Regulatory Capital Requirements and Bank's Capital Position (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Tier 1 Leverage ratio to Average Assets, actual amount	$ 46,752	$ 37,805
Tier 1 Leverage ratio to Average Assets, actual percentage	9.31%	9.28%
Tier 1 Leverage ratio to Average Assets, for capital adequacy purposes, amount	$ 20,084	$ 16,288
Tier 1 Leverage ratio to Average Assets, for capital adequacy purposes, percentage	4.00%	4.00%
Tier 1 Leverage ratio to Average Assets, for well capitalized purposes, amount	$ 25,105	$ 20,360
Tier 1 Leverage ratio to Average Assets, for well capitalized purposes, percentage	5.00%	5.00%
Common Equity Tier 1 Capital to Risk-Weighted Assets, actual amount	$ 46,752	$ 37,805
Common Equity Tier 1 Capital to Risk-Weighted Assets, actual percentage	13.24%	12.90%
Common Equity Tier 1 Capital to Risk-Weighted Assets, for capital adequacy purposes, amount	$ 15,885	$ 13,190
Common Equity Tier 1 Capital to Risk-Weighted Assets, for capital adequacy purposes, percentage	4.50%	4.50%
Common Equity Tier 1 Capital to Risk-Weighted Assets, for well capitalized purposes, amount	$ 22,945	$ 19,052
Common Equity Tier 1 Capital to Risk-Weighted Assets, for well capitalized purposes, percentage	6.50%	6.50%
Tier 1 Capital to Risk-Weighted Assets, actual amount	$ 46,752	$ 37,805
Tier 1 Capital to Risk-Weighted Assets, actual percentage	13.24%	12.90%
Tier 1 Capital to Risk-Weighted Assets, for capital adequacy purposes, amount	$ 21,180	$ 17,587
Tier 1 Capital to Risk-Weighted Assets, for capital adequacy purposes, percentage	6.00%	6.00%
Tier 1 Capital to Risk-Weighted Assets, for well capitalized purposes, amount	$ 28,240	$ 23,449
Tier 1 Capital to Risk-Weighted Assets, for well capitalized purposes, percentage	8.00%	8.00%
Total Capital to Risk-Weighted Assets, actual amount	$ 51,165	$ 41,466
Total Capital to Risk-Weighted Assets, actual percentage	14.49%	14.15%
Total Capital to Risk-Weighted Assets, for capital adequacy purposes, amount	$ 28,240	$ 23,449
Total Capital to Risk-Weighted Assets, for capital adequacy purposes, percentage	8.00%	8.00%
Total Capital to Risk-Weighted Assets, for well capitalized purposes, amount	$ 35,300	$ 29,311
Total Capital to Risk-Weighted Assets, for well capitalized purposes, percentage	10.00%	10.00%

Represents the Common Equity Tier 1 Capital (CET) capital required for capital adequacy to risk weighted assets.

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Represents Common Equity Tier 1 Capital (CET) capital be well capitalized to risk weighted assets.

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total 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 required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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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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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as well-capitalized under regulatory framework for prompt corrective action.

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

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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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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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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