Debt, Derivatives and Hedging Activities - Summary of Debt Outstanding (Details) - USD ($)	Aug. 31, 2017	May 31, 2017
Long-term Debt and Capital Lease Obligations, Current [Abstract]
Debt issuance costs	$ (50,000)	$ (100,000)
Total debt due within one year	307,450,000	362,900,000
Long-term Debt and Capital Lease Obligations [Abstract]
Debt issuance costs	(21,334,000)	(22,075,000)
Total debt due after one year	2,533,672,000	2,770,624,000
Senior notes \| Senior Notes, 6.13%, 2018 Maturity
Long-term Debt and Capital Lease Obligations, Current [Abstract]
Long-term Debt, current	$ 300,000,000	300,000,000
Long-term Debt and Capital Lease Obligations [Abstract]
Stated interest rate (as a percent)	6.13%
Senior notes \| Senior Notes 4.30%, 2022 Maturity
Long-term Debt and Capital Lease Obligations [Abstract]
Long-term Debt, non-current	$ 250,000,000	250,000,000
Stated interest rate (as a percent)	4.30%
Senior notes \| Senior Notes, 2.90%, 2022 Maturity
Long-term Debt and Capital Lease Obligations [Abstract]
Long-term Debt, non-current	$ 650,000,000	650,000,000
Stated interest rate (as a percent)	2.90%
Senior notes \| Senior Notes, 3.25%, 2023 Maturity
Long-term Debt and Capital Lease Obligations [Abstract]
Long-term Debt, non-current	$ 300,000,000	300,000,000
Stated interest rate (as a percent)	3.25%
Senior notes \| Senior Notes, 2.78%, 2023 Maturity
Long-term Debt and Capital Lease Obligations [Abstract]
Long-term Debt, non-current	$ 52,446,000	52,554,000
Stated interest rate (as a percent)	2.78%
Senior notes \| Senior Notes, 2.78%, 2023 Maturity \| G&K Services
Long-term Debt and Capital Lease Obligations [Abstract]
Face value		$ 50,000,000.0
Stated interest rate (as a percent)		3.73%
Senior notes \| Senior Notes, 3.11%, 2025 Maturity
Long-term Debt and Capital Lease Obligations [Abstract]
Long-term Debt, non-current	$ 52,560,000	$ 52,645,000
Stated interest rate (as a percent)	3.11%
Senior notes \| Senior Notes, 3.11%, 2025 Maturity \| G&K Services
Long-term Debt and Capital Lease Obligations [Abstract]
Face value		$ 50,000,000.0
Stated interest rate (as a percent)		3.88%
Senior notes \| Senior Notes, 3.70%, 2027 Maturity
Long-term Debt and Capital Lease Obligations [Abstract]
Long-term Debt, non-current	$ 1,000,000,000	$ 1,000,000,000
Stated interest rate (as a percent)	3.70%
Senior notes \| Senior Notes, 6.15%, 2037 Maturity
Long-term Debt and Capital Lease Obligations [Abstract]
Long-term Debt, non-current	$ 250,000,000	250,000,000
Stated interest rate (as a percent)	6.15%
Commercial paper \| Commercial Paper, 1.24%
Long-term Debt and Capital Lease Obligations, Current [Abstract]
Long-term Debt, current	$ 7,500,000	50,500,000
Long-term Debt and Capital Lease Obligations [Abstract]
Effective interest rate (as a percent)	1.40%
Line of Credit \| Term Loan Facility
Long-term Debt and Capital Lease Obligations, Current [Abstract]
Long-term Debt, current	$ 0	12,500,000
Long-term Debt and Capital Lease Obligations [Abstract]
Long-term Debt, non-current	$ 0	$ 237,500,000
Effective interest rate (as a percent)	2.00%

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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.

+ References

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-Name Accounting Standards Codification
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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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