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Income Taxes - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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May 31, 2018 | May 31, 2017 | May 31, 2016
Operating Loss Carryforwards [Line Items] |  |  |
Income taxes paid | $ 175.3 | $ 269.6 | $ 452.6
Unrecognized tax benefits that would impact effective tax rates if recognized | 26.9 | 12.6 |
Unrecognized tax benefits, interest and penalties accrued | 1.8 | $ 0.9 |
Revaluation of net deferred tax liability | 175.6 |  |
Provisional transition tax liability | 9.8 |  |
Foreign withholding taxes | 3.7 |  |
G & K Services |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Foreign withholding taxes | $ 0.7 |  |

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- Definition Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset Provisional Income Tax Expense + References No definition available. + Details
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- Definition The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586 + Details
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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