Note 10 - Securities Sold Under Agreements to Repurchase - Securities Sold Under Agreements to Repurchase (Details) - Securities Sold under Agreements to Repurchase [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Outstanding balance at end of period	$ 142,146		$ 75,466
Weighted average interest rate at end of period	0.08%		0.04%
Average outstanding balance during the period	$ 91,082	$ 46,937
Average interest rate during the period	0.08%	0.04%
Maximum outstanding at any month end during the period	$ 142,146	$ 51,681