Debt and Derivatives - Summary of Outstanding Debt (Details) - USD ($)	May 31, 2017	May 31, 2016
Debt due within one year
Debt issuance costs	$ (100,000)	$ 0
Total debt due within one year	362,900,000	250,000,000
Debt due after one year
Debt issuance costs	(22,075,000)	(5,578,000)
Total debt due after one year	2,770,624,000	1,044,422,000
Senior Notes, 2.85%, 2017 Maturity \| Senior notes
Debt due within one year
Long-term Debt, current	$ 0	250,000,000
Debt due after one year
Stated interest rate (as a percent)	2.85%
Senior Notes, 6.13%, 2018 Maturity \| Senior notes
Debt due within one year
Long-term Debt, current	$ 300,000,000	0
Debt due after one year
Long-term Debt, non-current	$ 0	300,000,000
Stated interest rate (as a percent)	6.13%
Commercial Paper, 1.24% \| Commercial paper
Debt due within one year
Long-term Debt, current	$ 50,500,000	0
Debt due after one year
Interest Rate (as a percent)	1.24%
Term Loan Facility \| Line of Credit
Debt due within one year
Long-term Debt, current	$ 12,500,000	0
Debt due after one year
Long-term Debt, non-current	$ 237,500,000	0
Interest Rate (as a percent)	2.00%
Senior Notes 4.30%, 2022 Maturity \| Senior notes
Debt due after one year
Long-term Debt, non-current	$ 250,000,000	250,000,000
Stated interest rate (as a percent)	4.30%
Senior Notes, 2.90%, 2022 Maturity \| Senior notes
Debt due after one year
Long-term Debt, non-current	$ 650,000,000	0
Stated interest rate (as a percent)	2.90%
Senior Notes, 3.25%, 2023 Maturity \| Senior notes
Debt due after one year
Long-term Debt, non-current	$ 300,000,000	250,000,000
Stated interest rate (as a percent)	3.25%
Senior Notes, 2.78%, 2023 Maturity \| Senior notes
Debt due after one year
Long-term Debt, non-current	$ 52,554,000	0
Interest Rate (as a percent)	2.78%
Senior Notes, 2.78%, 2023 Maturity \| Senior notes \| G & K Services
Debt due after one year
Face value	$ 50,000,000.0
Stated interest rate (as a percent)	3.73%
Senior Notes, 3.11%, 2025 Maturity \| Senior notes
Debt due after one year
Long-term Debt, non-current	$ 52,645,000	0
Interest Rate (as a percent)	3.11%
Senior Notes, 3.11%, 2025 Maturity \| Senior notes \| G & K Services
Debt due after one year
Face value	$ 50,000,000.0
Stated interest rate (as a percent)	3.88%
Senior Notes, 3.70%, 2027 Maturity \| Senior notes
Debt due after one year
Long-term Debt, non-current	$ 1,000,000,000	0
Stated interest rate (as a percent)	3.70%
Senior Notes, 6.15%, 2037 Maturity \| Senior notes
Debt due after one year
Long-term Debt, non-current	$ 250,000,000	$ 250,000,000
Stated interest rate (as a percent)	6.15%

Long-term Debt, Current Maturities, Gross

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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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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 accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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