Note 19 - Fair Value Measurements (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 0
Foreclosed Real Estate [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Write-down or Reserve, Amount	284,000	$ 419,000	$ 263,000
Fair Value, Inputs, Level 3 [Member] | Impaired Loan [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Write-down or Reserve, Amount	$ 22,000	$ 231,000	$ 39,000
Fair Value, Inputs, Level 3 [Member] | Impaired Loan [Member] | Minimum [Member]
Fair Value Inputs, Estimated Selling Costs	40.00%	20.00%
Fair Value, Inputs, Level 3 [Member] | Impaired Loan [Member] | Maximum [Member]
Fair Value Inputs, Estimated Selling Costs	66.00%	62.00%
Fair Value, Inputs, Level 3 [Member] | Impaired Loan [Member] | Weighted Average [Member]
Fair Value Inputs, Estimated Selling Costs	47.00%	39.00%
Fair Value, Inputs, Level 3 [Member] | Foreclosed Real Estate [Member]
Fair Value Inputs, Estimated Selling Costs	38.00%
Fair Value, Inputs, Level 3 [Member] | Foreclosed Real Estate [Member] | Minimum [Member]
Fair Value Inputs, Estimated Selling Costs		10.00%
Fair Value, Inputs, Level 3 [Member] | Foreclosed Real Estate [Member] | Maximum [Member]
Fair Value Inputs, Estimated Selling Costs		79.00%
Fair Value, Inputs, Level 3 [Member] | Foreclosed Real Estate [Member] | Weighted Average [Member]
Fair Value Inputs, Estimated Selling Costs		51.00%