Note 8 - Other Assets - Changes in the Net Carrying Amount of MSRs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Balance at beginning of period	$ 1,372	$ 1,022	$ 875
Additions for mortgage loans sold	1,785	506	302
Amortization	(447)	(156)	(155)
Balance at end of period	$ 2,710	$ 1,372	$ 1,022