Note 21 - Fair Value and Interest Rate Risk - Quantitative Information About Level 3 Fair Value Measurements (Details)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
SBA servicing assets	$ 316,000	$ 201,000
Fair Value, Inputs, Level 3 [Member]
SBA servicing assets		$ 280,000
Fair Value, Inputs, Level 3 [Member] | Minimum [Member] | Measurement Input, Discount Rate [Member]
SBA servicing assets		0.1473
Fair Value, Inputs, Level 3 [Member] | Maximum [Member] | Measurement Input, Discount Rate [Member]
SBA servicing assets		0.149
Fair Value, Inputs, Level 3 [Member] | Fair Value of Collateral Approach [Member]
Impaired loans, net	22,971,000	$ 18,132,000
Other Real Estate Owned	$ 1,906,000	$ 2,400,000
Fair Value, Inputs, Level 3 [Member] | Fair Value of Collateral Approach [Member] | Measurement Input, Discount Rate [Member]
Other Real Estate Owned	0.0584	0.12
Fair Value, Inputs, Level 3 [Member] | Fair Value of Collateral Approach [Member] | Minimum [Member] | Measurement Input, Discount Rate [Member]
Impaired loans, net	0.058	0.08
Fair Value, Inputs, Level 3 [Member] | Fair Value of Collateral Approach [Member] | Maximum [Member] | Measurement Input, Discount Rate [Member]
Impaired loans, net	0.2	0.2
Fair Value, Inputs, Level 3 [Member] | Valuation Technique, Discounted Cash Flow [Member]
SBA servicing assets	$ 375,000
Fair Value, Inputs, Level 3 [Member] | Valuation Technique, Discounted Cash Flow [Member] | Minimum [Member] | Measurement Input, Discount Rate [Member]
SBA servicing assets	0.1473
Fair Value, Inputs, Level 3 [Member] | Valuation Technique, Discounted Cash Flow [Member] | Maximum [Member] | Measurement Input, Discount Rate [Member]
SBA servicing assets	0.149