Debt and Derivatives - Summary of Outstanding Debt (Details) - USD ($)	May 31, 2020	May 31, 2019
Debt due within one year
Debt due within one year	$ 0	$ 312,264,000
Debt issuance costs	0	(236,000)
Debt due after one year
Debt issuance costs	(13,182,000)	(16,150,000)
Total debt due after one year	2,539,705,000	2,537,507,000
Term loan due 2020
Debt due within one year
Debt due within one year	$ 0	200,000,000
Debt due after one year
Effective interest rate	3.06%
Senior notes \| Senior Notes 4.30%, 2022 Maturity
Debt due after one year
Long-term debt, non-current	$ 250,000,000	250,000,000
Stated interest rate	4.30%
Senior notes \| Senior Notes, 2.90%, 2022 Maturity
Debt due after one year
Long-term debt, non-current	$ 650,000,000	650,000,000
Stated interest rate	2.90%
Senior notes \| Senior Notes, 3.25%, 2023 Maturity
Debt due after one year
Long-term debt, non-current	$ 300,000,000	300,000,000
Stated interest rate	3.25%
Senior notes \| Senior Notes, 2.78%, 2023 Maturity
Debt due after one year
Long-term debt, non-current	$ 51,250,000	51,684,000
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
Long-term debt, non-current	$ 51,637,000	51,973,000
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
Long-term debt, non-current	$ 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
Long-term debt, non-current	$ 250,000,000	250,000,000
Stated interest rate	6.15%
Commercial paper
Debt due within one year
Debt due within one year	$ 0	$ 112,500,000
Debt due after one year
Effective interest rate	2.68%

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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