Note 14 - Regulatory Matters & Subsequent Event - Risk-based Capital and Related Ratios (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2015	Dec. 31, 2014
Total capital (to risk-weighted assets), Amount	$ 133,406	$ 112,128
Total capital (to risk-weighted assets), Ratio	14.77%	12.17%
Total capital (to risk-weighted assets), Minimum required for capital adequacy purposes	8.00%	8.00%	8.00%
Total capital (to risk-weighted assets), Minimum required for capital adequacy purposes with conservation buffer	10.50%	9.875%
Total capital (to risk-weighted assets), To be well capitalized under prompt corrective action	10.00%	10.00%	10.00%
Tier I capital (to risk-weighted assets), Amount	$ 123,753	$ 102,354
Tier I capital (to risk-weighted assets), Ratio	13.70%	11.11%
Tier I capital (to risk-weighted assets), Minimum required for capital adequacy purposes	6.00%	6.00%	6.00%	4.00%
Tier I capital (to risk-weighted assets), Minimum required for capital adequacy purposes with conservation buffer	8.50%	7.875%
Tier I capital (to risk-weighted assets), To be well capitalized under prompt corrective action	8.00%	8.00%	8.00%	6.00%
Tier I common equity (to risk-weighted assets), Amount	$ 123,753	$ 102,354
Tier I common equity (to risk-weighted assets), Ratio	13.70%	11.11%
Tier I common equity (to risk-weighted assets), Minimum required for capital adequacy purposes	4.50%	4.50%	4.50%
Tier I common equity (to risk-weighted assets), Minimum required for capital adequacy purposes with conservation buffer	7.00%	6.375%
Tier I common equity (to risk-weighted assets), To be well capitalized under prompt corrective action	6.50%	6.50%	6.50%
Tier I capital (to average assets), Amount	$ 123,753	$ 102,354
Tier I capital (to average assets), Ratio	10.36%	8.27%
Tier I capital (to average assets), Minimum required for capital adequacy purposes	4.00%	4.00%	4.00%
Tier I capital (to average assets), Minimum required for capital adequacy purposes with conservation buffer	4.00%	4.00%
Tier I capital (to average assets), To be well capitalized under prompt corrective action	5.00%	5.00%	5.00%
Total risk-weighted assets, Amount	$ 903,172	$ 921,126
Total average assets, Amount	$ 1,194,789	$ 1,238,347

Amount of average assets as calculated in accordance with U.S. Federal regulatory capital standards.

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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, plus the capital conservation buffer (phased in at 0.625% annually).

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The minimum Common Equity Tier One Capital Ratio (common equity 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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No definition available.

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The Common Equity Tier 1 capital ratio (Common Equity Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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The minimum Common Equity Tier One Capital Ratio (Common Equity Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action, plus the fully phased-in capital conservation buffer (phased in at 0.625% annually).

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No definition available.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations, plus the capital conservation buffer (phased in at 0.625% annually).

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action, plus the fully phased in capital conservation buffer (phased in at 0.625% annually).

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No definition available.

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The amount of total capital as defined in the regulations.

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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 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 risk-weighted assets as calculated in accordance with U.S. Federal regulatory capital standards.

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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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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" 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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