Note 10 - Employee Benefits - Non-vested Option Awards Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Granted, shares (in shares)	39,000
Granted, weighted average grant date fair value (in dollars per share)	$ 6.63	$ 5.79	$ 4.29
Forfeited, shares (in shares)	(9,300)
Service Based Options [Member]
Beginning of period, nonvested, shares (in shares)	544,150
Beginning of period, nonvested, weighted average grant date fair value (in dollars per share)	$ 4.62
Nonvested, weighted average remaining contractual life (Year)	5 years	5 years 6 months
Granted, shares (in shares)	39,000
Granted, weighted average grant date fair value (in dollars per share)	$ 6.63
Granted, weighted average remaining contractual life (Year)	6 years 7 months 6 days
Vested, shares (in shares)	(167,550)
Vested, weighted average grant date fair value (in dollars per share)	$ 4.44
Vested, weighted average remaining contractual life (Year)	3 years 10 months 24 days
Forfeited, shares (in shares)	(9,300)
Forfeited, weighted average grant date fair value (in dollars per share)	$ 5.01
Forfeited, weighted average remaining contractual life (Year)	5 years 2 months 12 days
End of period, nonvested, shares (in shares)	406,300	544,150
End of period, nonvested, weighted average grant date fair value (in dollars per share)	$ 4.88	$ 4.62