Note 13 - Stockholders' Equity and Earnings Per Share - Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net income	$ 354,124	$ 360,642	$ 298,304
Basic EPS, income	$ 354,124	$ 360,642	$ 298,304
Basic EPS, income (in shares)	72,573,025	74,337,265	78,268,369
Basic EPS, income (in dollars per share)	$ 4.88	$ 4.85	$ 3.81
Effect of dilutive stock options and RSU (in shares)	289,603	327,470	302,269
Diluted EPS, income	$ 354,124	$ 360,642	$ 298,304
Diluted EPS, income (in shares)	72,862,628	74,664,735	78,570,638
Diluted EPS, income (in dollars per share)	$ 4.86	$ 4.83	$ 3.8