XML 87 R73.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Acquisitions and Divestitures - Schedule of Valuation and Amortization Period of Identifiable Intangible Assets (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
May 31, 2017 | May 31, 2016
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Preliminary Valuation | $ 529,235 | $ 55,694
G & K Services |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Preliminary Valuation | 536,000 |
G & K Services | Service contracts |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Preliminary Valuation | $ 519,000 |
Amortization Period (in years) | 15 years |
G & K Services | Trade names |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Preliminary Valuation | $ 17,000 |
Amortization Period (in years) | 3 years |

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_AcquiredFiniteLivedIntangibleAssetsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
Name: | us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition. + References No definition available. + Details
Name: | us-gaap_FinitelivedIntangibleAssetsAcquired1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=ctas_GKServicesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_ServicingContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_TradeNamesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |