Supplemental Guarantor Information - Condensed Consolidated Statements of Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 30, 2014	Aug. 31, 2014	Nov. 30, 2013	Aug. 31, 2013	Nov. 30, 2014	Nov. 30, 2013
Condensed Consolidating Financial Statements
Net income	$ 120,412us-gaap_NetIncomeLoss		$ 84,862us-gaap_NetIncomeLoss		$ 230,520us-gaap_NetIncomeLoss	$ 162,616us-gaap_NetIncomeLoss
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(9,778)		2,040		(11,893)	1,394
Change in fair value of derivatives	(21)		(189)		(4)	(189)
Amortization of interest rate lock agreements	488		488		976	976
Change in fair value of available-for-sale securities	3		(4)		3	(18)
Other comprehensive (loss) income	(9,308)	(1,610)	2,335	(172)	(10,918)	2,163
Comprehensive income	111,104us-gaap_ComprehensiveIncomeNetOfTax		87,197us-gaap_ComprehensiveIncomeNetOfTax		219,602us-gaap_ComprehensiveIncomeNetOfTax	164,779us-gaap_ComprehensiveIncomeNetOfTax
Cintas Corporation
Condensed Consolidating Financial Statements
Net income	120,412		84,862		230,520	162,616
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0		0		0	0
Change in fair value of derivatives	0		0		0	0
Amortization of interest rate lock agreements	0		0		0	0
Change in fair value of available-for-sale securities	0		0		0	0
Other comprehensive (loss) income	0		0		0	0
Comprehensive income	120,412		84,862		230,520	162,616
Corp. 2
Condensed Consolidating Financial Statements
Net income	46,334		25,272		79,484	50,953
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0		(2)		0	5
Change in fair value of derivatives	0		0		0	(189)
Amortization of interest rate lock agreements	488		488		976	976
Change in fair value of available-for-sale securities	0		0		0	0
Other comprehensive (loss) income	488		486		976	792
Comprehensive income	46,822		25,758		80,460	51,745
Subsidiary Guarantors
Condensed Consolidating Financial Statements
Net income	68,745		56,722		143,761	107,679
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0		0		0	0
Change in fair value of derivatives	0		0		0	0
Amortization of interest rate lock agreements	0		0		0	0
Change in fair value of available-for-sale securities	0		0		0	(13)
Other comprehensive (loss) income	0		0		0	(13)
Comprehensive income	68,745		56,722		143,761	107,666
Non- Guarantors
Condensed Consolidating Financial Statements
Net income	6,637		3,273		9,814	19,667
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(9,778)		2,042		(11,893)	1,389
Change in fair value of derivatives	(21)		(189)		(4)	0
Amortization of interest rate lock agreements	0		0		0	0
Change in fair value of available-for-sale securities	3		(4)		3	(5)
Other comprehensive (loss) income	(9,796)		1,849		(11,894)	1,384
Comprehensive income	(3,159)		5,122		(2,080)	21,051
Eliminations
Condensed Consolidating Financial Statements
Net income	(121,716)		(85,267)		(233,059)	(178,299)
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0		0		0	0
Change in fair value of derivatives	0		0		0	0
Amortization of interest rate lock agreements	0		0		0	0
Change in fair value of available-for-sale securities	0		0		0	0
Other comprehensive (loss) income	0		0		0	0
Comprehensive income	$ (121,716)		$ (85,267)		$ (233,059)	$ (178,299)

Other Comprehensive Income (Loss), Amortization of Interest Rate Lock Agreements, Net of Tax

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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