[Line Items] for Accounting Policies [Table]

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- Definition

Contribution to Partnership, Consideration Received, Cash

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Inventories, Useful Life, Maximum

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- Definition

Inventories, Useful Life, Minimum

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- Definition

Partnership, Ownership Percentage by Third Party

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

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-Name Accounting Standards Codification

-Topic 825

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-Section 50

-Paragraph 20

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

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Significant Accounting Policies - Narrative (Details) $ in Millions			3 Months Ended	12 Months Ended
	Apr. 30, 2014 USD ($)	Feb. 28, 2014	Aug. 30, 2014 segment	May. 31, 2015 USD ($) segment	May. 31, 2014 USD ($)
Accounting Policies [Line Items]
Number of reportable segments \| segment				3
Number of operating segments \| segment			4	3
Restricted cash				$ 43.0	$ 33.5
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 Contacts and Other Assets
Accounting Policies [Line Items]
Service contracts and other assets useful lives (years)				5 years
Maximum \| Service Contacts and Other Assets
Accounting Policies [Line Items]
Service contracts and other assets useful lives (years)				10 years
Segment Concentration \| Cintas Shredding \| Assets \| Cintas Document Management Services
Accounting Policies [Line Items]
Concentration risk, percentage		76.00%
Segment Concentration \| Cintas Shredding \| Revenue \| Cintas Document Management Services
Accounting Policies [Line Items]
Concentration risk, percentage		80.00%
Segment Concentration \| Cintas Shredding \| Income Before Income Taxes \| Cintas Document Management Services
Accounting Policies [Line Items]
Concentration risk, percentage		70.00%
Shred-it Partnership
Accounting Policies [Line Items]
Percentage of newly formed partnership owned by Cintas	42.00%
Contribution to partnership, cash consideration received	$ 180.0
Shred-it \| Shred-it Partnership
Accounting Policies [Line Items]
Partnership, ownership percentage by third party	58.00%