Note 15 - Earnings Per Common Share - Earnings Per Common Share (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Basic earnings per share (in shares)	10,873,817	10,981,623	10,531,572
Basic earnings per share (in dollars per share)	$ 4.00	$ 2.74	$ 1.99
Effect of dilutive securities - stock options (in shares)	3,414	4,167	9,765
Effect of dilutive securities - stock options (in dollars per share)	$ 0	$ (0.01)	$ (0.01)
Diluted earnings per share (in shares)	10,877,231	10,985,790	10,541,337
Diluted earnings per share (in dollars per share)	$ 4.00	$ 2.73	$ 1.98