Note 2 - Summary of Significant Accounting Policies - Basic and Diluted Earnings Per Share Computation (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Weighted average basic shares outstanding (in shares)	105,359	105,700	107,329
Effect of common stock equivalents (in shares)	1,234	1,066	978
Weighted average shares outstanding – diluted (in shares)	106,593	106,766	108,307