Note 2 - Accounting Policies - Earnings Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Weighted average number of common shares used for basic EPS (in shares)	30,731,882	31,130,222	32,345,382
Effect of dilutive stock options and restricted and deferred stock unit awards (in shares)	509,253	0	0
Weighted average number of common shares and dilutive potential common stock used for dilutive EPS (in shares)	31,241,135	31,130,222	32,345,382