Note 8 - Loans - Troubled Debt Restructuring Activity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Charge-offs	$ 0	$ 0	$ 0	$ 0
Accruing Troubled Debt Restructuring [Member]
Beginning balance	27,261	31,671	27,721	35,336
New restructurings	(208)	2,983	479	5,417
Restructured loans restored to accrual status	0	263	0	263
Charge-offs	0	0	0	0
Payments	(2,406)	(6,330)	(3,553)	(12,429)
Restructured loans placed on non-accrual status	(241)	0	(241)	0
Ending balance	24,406	28,587	24,406	28,587
Non-accruing Troubled Debt Restructuring [Member]
Beginning balance	8,402	12,670	8,985	18,048
New restructurings	0	0	0	0
Restructured loans restored to accrual status	234	0	241	0
Charge-offs	0	0	0	(4,970)
Payments	(352)	(2,488)	(710)	(2,896)
Restructured loans placed on non-accrual status	0	(263)	(232)	(263)
Ending balance	$ 8,284	$ 9,919	$ 8,284	$ 9,919