Note 6 - Fair Value Measurements and Fair Value of Financial Instruments - Assets Measured on a Nonrecurring Basis (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Commercial Portfolio Segment [Member]
Collateral dependent loans	$ 14,443	$ 13,399
Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member]
Collateral dependent loans	0	0
Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Collateral dependent loans	0	0
Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Collateral dependent loans	14,443	13,399
Commercial Real Estate Portfolio Segment [Member]
Collateral dependent loans	26,197	20,185
Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member]
Collateral dependent loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Collateral dependent loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Collateral dependent loans	26,197	20,185
Residential Portfolio Segment [Member]
Collateral dependent loans	1,372	2,794
Residential Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member]
Collateral dependent loans	0	0
Residential Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Collateral dependent loans	0	0
Residential Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Collateral dependent loans	$ 1,372	$ 2,794