Note 13 - Regulatory Capital and Oversight - Capital Amounts and Ratios (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Common equity tier 1 capital, actual amount	$ 81,642
Common equity tier 1 capital, actual percent of asset	13.31%	[1]
Common equity tier 1 capital, amount required to be adequately capitalized	$ 27,596
Common equity tier 1 capital, percent of assets required to be adequately capitalized	4.50%	[1]
Common equity tier 1 capital, excess capital amount	$ 54,046
Common equity tier 1 capital, excess capital percent of assets	8.81%	[1]
Common equity tier 1 capital, amount to be well capitalized under prompt corrective action provisions	$ 39,861
Common equity tier 1 capital, percent of assets to be well capitalized under prompt corrective action provisions	6.50%	[1]
Tier 1 leverage, actual amount	$ 81,642
Tier 1 leverage, actual percent of asset	11.00%
Tier 1 leverage, amount required to be adequately capitalized	$ 29,679
Tier 1 leverage, percent of assets required to be adequately capitalized	4.00%
Tier 1 leverage, excess capital amount	$ 51,963
Tier 1 leverage, excess capital percent of assets	7.00%
Tier 1 leverage, amount to be well capitalized under prompt corrective action provisions	$ 37,098
Tier 1 leverage, percent of assets to be well capitalized under prompt corrective action provisions	5.00%
Tier 1 risk-based capital, actual amount	$ 81,642
Tier 1 risk-based capital, actual percent of asset	13.31%	[1]
Tier 1 risk-based capital, amount required to be adequately capitalized	$ 36,795
Tier 1 risk-based capital, percent of assets required to be adequately capitalized	6.00%	[1]
Tier 1 risk-based capital, excess capital amount	$ 44,847
Tier 1 risk-based capital, excess capital percent of assets	7.31%	[1]
Tier 1 risk-based capital, amount to be well capitalized under prompt corrective action provisions	$ 49,060
Tier 1 risk-based capital, percent of assets to be well capitalized under prompt corrective action provisions	8.00%	[1]
Total risk-based capital, actual amount	$ 89,314
Total risk-based capital, actual percent of asset	14.56%	[1]
Total risk-based capital, amount required to be adequately capitalized	$ 49,060
Total risk-based capital, percent of assets required to be adequately capitalized	8.00%	[1]
Total risk-based capital, excess capital amount	$ 40,254
Total risk-based capital, excess capital percent of assets	6.56%	[1]
Total risk-based capital, amount to be well capitalized under prompt corrective action provisions	$ 61,325
Total risk-based capital, percent of assets to be well capitalized under prompt corrective action provisions	10.00%	[1]

[1] Based upon the Bank's adjusted total assets for the purpose of the Tier 1 leverage capital ratio and risk-weighted assets for the purpose of the risk-based capital ratios.