Note 7 - Share-based Compensation - Restricted Stock Transactions (Details) - Restricted Stock [Member]	6 Months Ended
	Jun. 30, 2022 $ / shares shares
Outstanding (in shares) | shares	458,166
Outstanding, weighted average grant date fair value (in dollars per share) | $ / shares	$ 19.51
Granted (in shares) | shares	30,343
Granted, weighted average grant date fair value (in dollars per share) | $ / shares	$ 19.97
Vested (in shares) | shares	(113,039)
Vested, weighted average grant date fair value (in dollars per share) | $ / shares	$ 15.22
Forfeited (in shares) | shares	(8,500)
Forfeited, weighted average grant date fair value (in dollars per share) | $ / shares	$ 13.11
Outstanding (in shares) | shares	366,970
Outstanding, weighted average grant date fair value (in dollars per share) | $ / shares	$ 21.02