Note 2 - Investment Securities - Continuous Unrealized Loss Positions (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Less than 12 months, fair value	$ 67,190	$ 3,694
Less than 12 months, unrealized losses	(1,235)	(31)
12 months or more, fair value	1,509	0
12 months or more, unrealized losses	(26)	0
Fair value	68,699	3,694
Unrealized losses	(1,261)	(31)
US Government Agencies Debt Securities [Member]
Less than 12 months, fair value	10,927	0
Less than 12 months, unrealized losses	(84)	0
12 months or more, fair value	0	0
12 months or more, unrealized losses	0	0
Fair value	10,927	0
Unrealized losses	(84)	0
Collateralized Mortgage Backed Securities [Member]
Less than 12 months, fair value	40,501	0
Less than 12 months, unrealized losses	(795)	0
12 months or more, fair value	0	0
12 months or more, unrealized losses	0	0
Fair value	40,501	0
Unrealized losses	(795)	0
Corporate Debt Securities [Member]
Less than 12 months, fair value	0	0
Less than 12 months, unrealized losses	0	0
12 months or more, fair value	0	0
12 months or more, unrealized losses	0	0
Fair value	0	0
Unrealized losses	0	0
US States and Political Subdivisions Debt Securities [Member]
Less than 12 months, fair value	15,762	3,694
Less than 12 months, unrealized losses	(356)	(31)
12 months or more, fair value	1,509	0
12 months or more, unrealized losses	(26)	0
Fair value	17,271	3,694
Unrealized losses	$ (382)	$ (31)