Debt, Derivatives and Hedging Activities - Summary of Debt Outstanding (Details) - USD ($)	Nov. 30, 2020	May 31, 2020
Debt due within one year
Debt issuance costs	$ (128,000)	$ 0
Debt due within one year	249,872,000	0
Debt due after one year
Debt issuance costs	(11,569,000)	(13,182,000)
Total debt due after one year	2,290,932,000	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 after one year
Debt due after one year, gross	$ 650,000,000	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	$ 51,032,000	51,250,000
Stated 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	$ 51,469,000	51,637,000
Stated 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, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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