Earnings Per Share - Schedule of Buyback Activity by Program (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Nov. 30, 2024	Aug. 31, 2024	Nov. 30, 2023	Aug. 31, 2023	Nov. 30, 2024	Nov. 30, 2023
Equity, Class of Treasury Stock [Line Items]
Purchase Price	$ 36,716	$ 614,802	$ 349,852	$ 73,276
Shares acquired for taxes due (in shares)	174		228		918	810
Shares acquired for taxes due, average price (in dollars per share)	$ 211.44		$ 129.69		$ 193.79	$ 126.89
Shares acquired for taxes due	$ 36,716		$ 29,586		$ 177,901	$ 102,862
Total repurchase of Cintas common stock	$ 36,716		$ 349,852		$ 651,518	$ 423,128
Share Buyback Programs
Equity, Class of Treasury Stock [Line Items]
Shares (in shares)	0		2,633		2,732	2,633
Average Price per Share (in dollars per share)	$ 0		$ 121.64		$ 173.40	$ 121.64
Purchase Price	$ 0		$ 320,266		$ 473,617	$ 320,266
July 27, 2021 Plan
Equity, Class of Treasury Stock [Line Items]
Shares (in shares)	0		2,633		0	2,633
Average Price per Share (in dollars per share)	$ 0		$ 121.64		$ 0	$ 121.64
Purchase Price	$ 0		$ 320,266		$ 0	$ 320,266
July 26, 2022 Plan
Equity, Class of Treasury Stock [Line Items]
Shares (in shares)	0		0		2,732	0
Average Price per Share (in dollars per share)	$ 0		$ 0		$ 173.40	$ 0
Purchase Price	$ 0		$ 0		$ 473,617	$ 0
July 23, 2024 Plan
Equity, Class of Treasury Stock [Line Items]
Shares (in shares)	0		0		0	0
Average Price per Share (in dollars per share)	$ 0		$ 0		$ 0	$ 0
Purchase Price	$ 0		$ 0		$ 0	$ 0