Earnings per Share - Computation of EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	May 31, 2023	May 31, 2022	May 31, 2021
Basic Earnings per Share from Continuing Operations
Net income	$ 1,348,010	$ 1,235,757	$ 1,110,968
Less: net income allocated to participating securities	5,463	6,132	7,623
Net income available to common shareholders	$ 1,342,547	$ 1,229,625	$ 1,103,345
Basic weighted average common shares outstanding (in shares)	101,645	103,172	104,874
Basic earnings per share from continuing operations (in dollars per share)	$ 13.21	$ 11.92	$ 10.52
Diluted Earnings per Share from Continuing Operations
Net income	$ 1,348,010	$ 1,235,757	$ 1,110,968
Less: net income allocated to participating securities	5,463	6,132	7,623
Net income available to common shareholders	$ 1,342,547	$ 1,229,625	$ 1,103,345
Basic weighted average common shares outstanding (in shares)	101,645	103,172	104,874
Effect of dilutive securities - employee stock options (in shares)	1,732	2,351	2,833
Diluted weighted average common shares outstanding (in shares)	103,377	105,523	107,707
Diluted earnings per share from continuing operations (in dollars per share)	$ 12.99	$ 11.65	$ 10.24