Note 12 - Regulatory Capital - Capital Amounts and Ratios (Details) $ in Thousands	Jun. 30, 2018 USD ($)
Common equity tier 1 capital, actual amount	$ 79,826
Common equity tier 1 capital, actual percent of asset	12.88%
Common equity tier 1 capital, amount required to be adequately capitalized	$ 27,900
Common equity tier 1 capital, percent of assets required to be adequately capitalized	4.50%
Common equity tier 1 capital, excess capital amount	$ 51,926
Common equity tier 1 capital, excess capital percent of assets	8.38%
Common equity tier 1 capital, amount to be well capitalized under prompt corrective action provisions	$ 40,300
Common equity tier 1 capital, percent of assets to be well capitalized under prompt corrective action provisions	6.50%
Tier 1 capital leverage, actual amount	$ 79,826
Tier 1 capital leverage, actual percent of asset	11.02%
Tier 1 capital leverage, amount required to be adequately capitalized	$ 28,968
Tier 1 capital leverage, percent of assets required to be adequately capitalized	4.00%
Tier 1 capital leverage, excess capital amount	$ 50,858
Tier 1 capital leverage, excess capital percent of assets	7.02%
Tier 1 capital leverage, amount to be well capitalized under prompt corrective action provisions	$ 36,210
Tier 1 capital leverage, percent of assets to be well capitalized under prompt corrective action provisions	5.00%
Tier 1 risk-based capital, actual amount	$ 79,826
Tier 1 risk-based capital, actual percent of asset	12.88%
Tier 1 risk-based capital, amount required to be adequately capitalized	$ 37,200
Tier 1 risk-based capital, percent of assets required to be adequately capitalized	6.00%
Tier 1 risk-based capital, excess capital amount	$ 42,626
Tier 1 risk-based capital, excess capital percent of assets	6.88%
Tier 1 risk-based capital, amount to be well capitalized under prompt corrective action provisions	$ 49,600
Tier 1 risk-based capital, percent of assets to be well capitalized under prompt corrective action provisions	8.00%
Total risk-based capital, actual amount	$ 87,595
Total risk-based capital, actual percent of asset	14.13%
Total risk-based capital, amount required to be adequately capitalized	$ 49,600
Total risk-based capital, percent of assets required to be adequately capitalized	8.00%
Total risk-based capital, excess capital amount	$ 37,995
Total risk-based capital, excess capital percent of assets	6.13%
Total risk-based capital, amount to be well capitalized under prompt corrective action provisions	$ 62,000
Total risk-based capital, percent of assets to be well capitalized under prompt corrective action provisions	10.00%