Earnings per Share - Schedule of Buyback Activity by Program (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended			34 Months Ended
	May 31, 2024	May 31, 2023	May 31, 2022	May 31, 2024
Equity, Class of Treasury Stock [Line Items]
Purchase Price	$ 700,033	$ 398,865	$ 1,525,873
Shares acquired for taxes due (in shares)	331	430	305
Shares acquired for taxes due, average price (in dollars per share)	$ 557.34	$ 420.21	$ 397.16
Shares acquired for taxes due	$ 184,645	$ 180,577	$ 121,224
Total repurchase of Cintas common stock	$ 700,033	$ 398,865	$ 1,525,873
Share Repurchase Programs
Equity, Class of Treasury Stock [Line Items]
Shares (in shares)	941	550	3,740
Average Price per Share (in dollars per share)	$ 547.69	$ 396.69	$ 375.53
Purchase Price	$ 515,388	$ 218,288	$ 1,404,649
Share Buyback Program October 2019
Equity, Class of Treasury Stock [Line Items]
Shares (in shares)	0	0	1,590
Average Price per Share (in dollars per share)	$ 0	$ 0	$ 365.41
Purchase Price	$ 0	$ 0	$ 581,220
Share Buyback Program July 27 2021
Equity, Class of Treasury Stock [Line Items]
Shares (in shares)	856	550	2,150	3,600
Average Price per Share (in dollars per share)	$ 535.21	$ 396.69	$ 383.01	$ 421.77
Purchase Price	$ 458,284	$ 218,288	$ 823,429	$ 1,500,000
Share Buyback Program July 26 2022
Equity, Class of Treasury Stock [Line Items]
Shares (in shares)	85	0	0
Average Price per Share (in dollars per share)	$ 673.78	$ 0	$ 0
Purchase Price	$ 57,104	$ 0	$ 0