Note 3 - Earnings Per Share - Earnings Per Share Calculation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Numerator for basic and diluted earnings per share – Net income available to common shareholders	$ 71,608	$ 90,455
Denominator for basic earnings per share – weighted average shares outstanding (in shares)	78,483	82,150
Effect of dilutive securities– Employee stock options and restricted share awards (in shares)	2,971	2,696
Denominator for diluted earnings per share – adjusted weighted average shares outstanding and assumed conversions (in shares)	81,454	84,846
Basic earnings per common share (in dollars per share)	$ 0.91	$ 1.1
Diluted earnings per common share and common share equivalents (in dollars per share)	$ 0.88	$ 1.07