Note 13 - Regulatory Capital - Capital Regulatory Ratios (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Total risk based capital
Capital	$ 249,510	$ 245,043
Capital to risk-weighted assets	16.70%	18.99%
Capital required for capital adequacy	$ 119,521	$ 103,226
Capital required for capital adequacy to risk-weighted assets	8.00%	8.00%
Capital required for capital adequacy, with capital buffer	$ 138,197	$ 111,290
Total capital (to risk-weighted assets)	9.25%	8.625%
Capital required to be well capitalized
Capital required to be well capitalized to risk-weighted assets
Tier one risk based capital
Tier one risk-based capital	$ 240,911	$ 235,888
Tier one risk-based capital to risk-weighted assets	16.13%	18.28%
Tier one risk-based capital required for capital adequacy	$ 89,641	$ 77,419
Tier one risk-based capital required for capital adequacy to risk-weighted assets	6.00%	6.00%
Tier one risk-based capital required for capital adequacy, with capital buffer	$ 108,316	$ 85,484
Tier 1 capital (to risk weighted assets)	7.25%	6.625%
Tier one risk-based capital required to be well capitalized
Tier one risk-based capital required to be well capitalized to risk-weighted assets
CET 1 risk based capital
Common equity tier one risk-based capital	$ 220,433	$ 214,088
Common equity tier one risk-based capital to risk-weighted assets	14.75%	16.59%
Common equity tier one risk-based capital required for capital adequacy	$ 67,231	$ 58,064
Common equity tier one risk-based capital required for capital adequacy to risk-weighted assets	4.50%	4.50%
Common equity tier one risk-based capital required for capital adequacy, with capital buffer	$ 85,906	$ 66,129
Common equity tier 1 capital (CET1)	5.75%	5.125%
Common equity tier one risk-based capital required to be well capitalized
Common equity tier one risk-based capital required to be well capitalized to risk-weighted assets
Tier one leveraged capital
Tier one leverage capital	$ 240,911	$ 235,888
Tier one leverage capital to average assets	10.64%	12.74%
Tier one leverage capital required for capital adequacy	$ 90,586	$ 74,073
Tier one leverage capital required for capital adequacy to risk average assets	4.00%	4.00%
Tier one leverage capital required for capital adequacy, with capital buffer	$ 90,586	$ 74,073
Tier one leverage capitalrequired for capital adequacy to average assets, with capital buffer	4.00%	4.00%
Tier one leverage capitalrequired to be well capitalized
Tier one leverage capitalrequired to be well capitalized to average assets
Subsidiaries [Member]
Total risk based capital
Capital	$ 187,732	$ 179,057
Capital to risk-weighted assets	12.57%	13.93%
Capital required for capital adequacy	$ 119,446	$ 102,811
Capital required for capital adequacy to risk-weighted assets	8.00%	8.00%
Capital required for capital adequacy, with capital buffer	$ 138,109	$ 110,843
Total capital (to risk-weighted assets)	9.25%	8.625%
Capital required to be well capitalized	$ 149,307	$ 128,514
Capital required to be well capitalized to risk-weighted assets	10.00%	10.00%
Tier one risk based capital
Tier one risk-based capital	$ 179,133	$ 169,902
Tier one risk-based capital to risk-weighted assets	12.00%	13.22%
Tier one risk-based capital required for capital adequacy	$ 89,584	$ 77,108
Tier one risk-based capital required for capital adequacy to risk-weighted assets	6.00%	6.00%
Tier one risk-based capital required for capital adequacy, with capital buffer	$ 108,248	$ 85,140
Tier 1 capital (to risk weighted assets)	7.25%	6.625%
Tier one risk-based capital required to be well capitalized	$ 119,446	$ 102,811
Tier one risk-based capital required to be well capitalized to risk-weighted assets	8.00%	8.00%
CET 1 risk based capital
Common equity tier one risk-based capital	$ 179,133	$ 169,902
Common equity tier one risk-based capital to risk-weighted assets	12.00%	13.22%
Common equity tier one risk-based capital required for capital adequacy	$ 67,188	$ 57,831
Common equity tier one risk-based capital required for capital adequacy to risk-weighted assets	4.50%	4.50%
Common equity tier one risk-based capital required for capital adequacy, with capital buffer	$ 85,852	$ 65,863
Common equity tier 1 capital (CET1)	5.75%	5.125%
Common equity tier one risk-based capital required to be well capitalized	$ 97,050	$ 83,534
Common equity tier one risk-based capital required to be well capitalized to risk-weighted assets	6.50%	6.50%
Tier one leveraged capital
Tier one leverage capital	$ 179,133	$ 169,902
Tier one leverage capital to average assets	7.91%	9.20%
Tier one leverage capital required for capital adequacy	$ 90,531	$ 73,843
Tier one leverage capital required for capital adequacy to risk average assets	4.00%	4.00%
Tier one leverage capital required for capital adequacy, with capital buffer	$ 90,531	$ 73,843
Tier one leverage capitalrequired for capital adequacy to average assets, with capital buffer	4.00%	4.00%
Tier one leverage capitalrequired to be well capitalized	$ 113,164	$ 92,304
Tier one leverage capitalrequired to be well capitalized to average assets	5.00%	5.00%

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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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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets and increased by a capital buffer, as defined in the regulations.

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The amount of total capital as defined in the regulations.

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

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

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