Note 11 - Capital Ratios and Regulatory Minimum Requirements (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
The Company [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Capital	$ 128,004	$ 120,379
Tier 1 capital	118,437	111,472
Common equity tier 1 capital	118,437	111,472
Tier 1 leverage capital	$ 118,437	$ 111,472
Capital to risk-weighted assets	13.62%	13.21%
Tier 1 capital to risk-weighted assets	12.60%	12.23%
Common equity tier 1 capital to risk-weighted assets	12.60%	12.23%
Tier 1 leverage capital to average assets	9.66%	9.40%
Capital required for capital adequacy	$ 75,199	$ 72,910
Tier 1 capital required for capital adequacy	56,399	54,682
Common equity tier 1 capital required for capital adequacy	42,299	41,012
Tier 1 leverage capital required for capital adequacy	$ 49,031	$ 47,458
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	$ 93,998	$ 91,137
Tier 1 capital required to be well capitalized	$ 56,399	$ 54,682
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	$ 116,583	$ 110,508
Tier 1 capital	107,016	101,601
Common equity tier 1 capital	107,016	101,601
Tier 1 leverage capital	$ 107,016	$ 101,601
Capital to risk-weighted assets	12.64%	12.52%
Tier 1 capital to risk-weighted assets	11.60%	11.51%
Common equity tier 1 capital to risk-weighted assets	11.60%	11.51%
Tier 1 leverage capital to average assets	8.81%	8.64%
Capital required for capital adequacy	$ 73,796	$ 70,619
Tier 1 capital required for capital adequacy	55,347	52,964
Common equity tier 1 capital required for capital adequacy	41,510	39,723
Tier 1 leverage capital required for capital adequacy	$ 48,581	$ 47,045
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	$ 92,245	$ 88,273
Tier 1 capital required to be well capitalized	73,796	70,619
Common equity tier 1 capital required to be well capitalized	59,959	57,378
Tier 1 leverage capital required to be well capitalized	$ 60,726	$ 58,807
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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