Note 13 - Employee Benefit Plans - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Options outstanding at beginning of period (in shares)	147,200
Options outstanding at beginning of period (in dollars per share)	$ 21.10
Granted (in shares)	0	0
Granted (in dollars per share)	$ 0
Exercised (in shares)	0	(8,459)	(24,186)
Exercised (in dollars per share)	$ 0
Canceled/Expired (in shares)	(32,921)
Canceled/Expired (in dollars per share)	$ 26.44
Options outstanding at end of period (in shares)	114,279	147,200
Options outstanding at end of period (in dollars per share)	$ 19.56	$ 21.10
Options outstanding at end of period (Year)	4 years 6 months 7 days
Options outstanding at end of period	$ 432
Options exercisable at end of period (in shares)	114,279
Options exercisable at end of period (in dollars per share)	$ 19.56
Options exercisable at end of period (Year)	4 years 6 months 7 days
Options exercisable at end of period	$ 432