Note 8 - Short-term Borrowings - Components of Short-term Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Short-term borrowings	$ 0	$ 117,000
Maximum outstanding at any month end	130,120	149,010
Average Outstanding Amount	32,446	49,860
Overnight Borrowings [Member]
Short-term borrowings	0	60,000
Maximum outstanding at any month end	73,120	92,000
Average Outstanding Amount	$ 4,121	$ 22,148
Weighted Average Interest Rate	5.52%	5.08%
Interest Rate At Year End	0.00%	5.50%
Other Short-term Borrowings [Member]
Short-term borrowings	$ 0	$ 57,000
Maximum outstanding at any month end		10
Average Outstanding Amount		5
Federal Reserve Bank Term Funding Program [Member]
Maximum outstanding at any month end	57,000	57,000
Average Outstanding Amount	$ 28,325	$ 27,707
Weighted Average Interest Rate	4.69%	4.49%
Interest Rate At Year End	0.00%	4.59%