Note 11 - Share-based Incentive Plan (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Jan. 23, 2012	Dec. 31, 2006
Shares Issued, Price Per Share (in dollars per share)				$ 19.00
Share-based Payment Arrangement, Expense	$ 300	$ 160
Restricted Stock [Member]
Shares Issued, Price Per Share (in dollars per share)					$ 20.00
Nonvested Resctricted Stock [Member]
Restricted Stock, Value, Shares Issued Net of Tax Withholdings	$ 2,300		$ 900
Minimum [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	3 years
Minimum [Member] | Nonvested Resctricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	1 year
Maximum [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	10 years
Maximum [Member] | Nonvested Resctricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	7 years