Earnings Per Share - Computation of EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Aug. 31, 2023	Aug. 31, 2022
Basic earnings per share:
Net income	$ 385,085	$ 351,689
Less: net income allocated to participating securities	1,560	1,520
Net income available to common shareholders	$ 383,525	$ 350,169
Basic weighted average common shares outstanding (in shares)	101,895	101,428
Basic earnings per share (in dollars per share)	$ 3.76	$ 3.45
Diluted earnings per share:
Net income	$ 385,085	$ 351,689
Less: net income allocated to participating securities	1,560	1,520
Net income available to common shareholders	$ 383,525	$ 350,169
Basic weighted average common shares outstanding (in shares)	101,895	101,428
Effect of dilutive securities - employee stock options (in shares)	1,677	1,909
Diluted weighted average common shares outstanding (in shares)	103,572	103,337
Diluted earnings per share (in dollars per share)	$ 3.70	$ 3.39