Debt and Derivatives - Summary of Outstanding Debt (Details) - USD ($)	May 31, 2021	May 31, 2020
Debt due within one year
Debt issuance costs	$ (930,000)	$ 0
Total debt due within one year	899,070,000	0
Debt due after one year
Debt issuance costs	(9,283,000)	(13,182,000)
Total debt due after one year	1,642,833,000	2,539,705,000
Senior notes \| Senior Notes 4.30%, 2022 Maturity
Debt due within one year
Debt due within one year, gross	250,000,000	0
Debt due after one year
Debt due after one year, gross	$ 0	250,000,000
Stated interest rate	4.30%
Senior notes \| Senior Notes, 2.90%, 2022 Maturity
Debt due within one year
Debt due within one year, gross	$ 650,000,000	0
Debt due after one year
Debt due after one year, gross	$ 0	650,000,000
Stated interest rate	2.90%
Senior notes \| Senior Notes, 3.25%, 2023 Maturity
Debt due after one year
Debt due after one year, gross	$ 300,000,000	300,000,000
Stated interest rate	3.25%
Senior notes \| Senior Notes, 2.78%, 2023 Maturity
Debt due after one year
Debt due after one year, gross	$ 50,815,000	51,250,000
Effective interest rate	2.78%
Senior notes \| Senior Notes, 2.78%, 2023 Maturity \| G & K Services
Debt due after one year
Stated interest rate	3.73%
Face value	$ 50,000,000.0
Senior notes \| Senior Notes, 3.11%, 2025 Maturity
Debt due after one year
Debt due after one year, gross	$ 51,301,000	51,637,000
Effective interest rate	3.11%
Senior notes \| Senior Notes, 3.11%, 2025 Maturity \| G & K Services
Debt due after one year
Stated interest rate	3.88%
Face value	$ 50,000,000.0
Senior notes \| Senior Notes, 3.70%, 2027 Maturity
Debt due after one year
Debt due after one year, gross	$ 1,000,000,000	1,000,000,000
Stated interest rate	3.70%
Senior notes \| Senior Notes, 6.15%, 2037 Maturity
Debt due after one year
Debt due after one year, gross	$ 250,000,000	$ 250,000,000
Stated interest rate	6.15%

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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