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Significant Accounting Policies - Narrative (Details) | 12 Months Ended |
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May 31, 2019 USD ($) segment business | May 31, 2018 USD ($) | May 31, 2017 USD ($) | Jun. 01, 2019 USD ($)
Accounting Policies [Line Items] |  |  |  |
Number of businesses helped | business | 1,000,000 |  |  |
Restricted cash | $ 31,400,000 | $ 30,900,000 |  |
Inventory obsolescence reserve | $ 32,700,000 | 37,000,000 |  |
Number of reporting units | segment | 4 |  |  |
Impairment of intangible assets | $ 0 | $ 0 | $ 0 |
Accounting Standards Update 2016-02 |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Lease right-of-use assets |  |  |  | $ 160,000,000
Lease liabilities |  |  |  | $ 185,000,000
Uniforms in service |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Inventories useful life, maximum | 18 months |  |  |
Other rental items |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Inventories useful life, minimum | 8 months |  |  |
Inventories useful life, maximum | 60 months |  |  |
Minimum | Service contracts and other assets |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Service contracts and other assets useful lives (years) | 5 years |  |  |
Maximum | Service contracts and other assets |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Service contracts and other assets useful lives (years) | 10 years |  |  |
All Other |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Number of reporting units | segment | 2 |  |  |
G & K Services | Service contracts |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Service contracts and other assets useful lives (years) | 15 years |  |  |

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