Note 9 - Fair Value Measurements - Assets Measured at Fair Value on a Nonrecurring Basis (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Fair Value	$ 110	$ 225
Total Losses	0	0
Fair Value, Inputs, Level 1 [Member]
Fair Value	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value	0	0
Fair Value, Inputs, Level 3 [Member]
Fair Value	110	225
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member]
Fair Value	110	225
Total Losses	0	0
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value	0	0
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value	0	0
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value	$ 110	$ 225