Note 11 - Capital Ratios and Regulatory Minimum Requirements (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
The Company [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Capital	$ 130,164	$ 130,412
Tier 1 capital	119,757	120,452
Common equity tier 1 capital	119,757	120,452
Tier 1 leverage capital	$ 119,757	$ 120,452
Capital to risk-weighted assets	13.87%	13.82%
Tier 1 capital to risk-weighted assets	12.76%	12.76%
Common equity tier 1 capital to risk-weighted assets	12.76%	12.76%
Tier 1 leverage capital to average assets	9.80%	9.78%
Capital required for capital adequacy	$ 75,059	$ 75,498
Tier 1 capital required for capital adequacy	56,294	56,624
Common equity tier 1 capital required for capital adequacy	42,220	42,468
Tier 1 leverage capital required for capital adequacy	$ 48,859	$ 49,283
Capital required for capital adequacy to risk-weighted assets	8.00%	8.00%
Tier 1 capital required for capital adequacy to risk-weighted assets	6.00%	6.00%
Common equity tier 1 capital required for capital adequacy to risk-weighted assets	4.50%	4.50%
Tier 1 leverage capital required for capital adequacy to average assets	4.00%	4.00%
Capital required to be well capitalized	$ 93,823	$ 94,373
Tier 1 capital required to be well capitalized	$ 56,294	$ 56,624
Capital required to be well capitalized to risk-weighted assets	10.00%	10.00%
Tier 1 capital required to be well capitalized to risk-weighted assets	6.00%	6.00%
Bank [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Capital	$ 120,148	$ 118,389
Tier 1 capital	109,741	108,429
Common equity tier 1 capital	109,741	108,429
Tier 1 leverage capital	$ 109,741	$ 108,429
Capital to risk-weighted assets	13.20%	12.93%
Tier 1 capital to risk-weighted assets	12.06%	11.84%
Common equity tier 1 capital to risk-weighted assets	12.06%	11.84%
Tier 1 leverage capital to average assets	9.07%	8.89%
Capital required for capital adequacy	$ 72,816	$ 73,270
Tier 1 capital required for capital adequacy	54,612	54,952
Common equity tier 1 capital required for capital adequacy	40,959	41,241
Tier 1 leverage capital required for capital adequacy	$ 48,372	$ 48,804
Capital required for capital adequacy to risk-weighted assets	8.00%	8.00%
Tier 1 capital required for capital adequacy to risk-weighted assets	6.00%	6.00%
Common equity tier 1 capital required for capital adequacy to risk-weighted assets	4.50%	4.50%
Tier 1 leverage capital required for capital adequacy to average assets	4.00%	4.00%
Capital required to be well capitalized	$ 91,019	$ 91,587
Tier 1 capital required to be well capitalized	72,816	73,270
Common equity tier 1 capital required to be well capitalized	59,163	59,532
Tier 1 leverage capital required to be well capitalized	$ 60,465	$ 61,005
Capital required to be well capitalized to risk-weighted assets	10.00%	10.00%
Tier 1 capital required to be well capitalized to risk-weighted assets	8.00%	8.00%
Common equity tier 1 capital required to be well capitalized to risk-weighted assets	6.50%	6.50%
Tier 1 leverage capital required to be well capitalized to average assets	5.00%	5.00%

Common equity tier 1 capital as defined in the regulations.

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Common equity tier 1 capital to risk-weighted assets as defined in regulations.

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The minimum amount of common equity tier 1 capital 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 minimum common equity tier 1 capital (common equity 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 amount of common equity tier 1 capital required to be categorized as well capitalized 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 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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 for capital adequacy purposes divided by average assets as defined in the regulations.

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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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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.

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

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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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