Note 6 - Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Net book value, balance	$ 2,359
Net book value, balance	1,898	$ 2,359
Core Deposits [Member]
Net book value, balance	2,359	3,070
Amortization expense	(461)	(711)
Net book value, balance	$ 1,898	$ 2,359