Supplemental Guarantor Information - Condensed Consolidating Statements of Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
Aug. 31, 2016	Aug. 31, 2015
Condensed Consolidating Financial Statements
Net income	$ 138,091	$ 100,181
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	115	(12,013)
Change in fair value of derivatives	(12,037)	0
Amortization of interest rate lock agreements	385	488
Change in fair value of available-for-sale securities	(1)	(8)
Other comprehensive loss	(11,538)	(11,533)
Comprehensive income	126,553	88,648
Eliminations
Condensed Consolidating Financial Statements
Net income	(135,265)	(101,804)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(115)	0
Change in fair value of derivatives	12,037
Amortization of interest rate lock agreements	(385)	0
Change in fair value of available-for-sale securities	1	0
Other comprehensive loss	11,538	0
Comprehensive income	(123,727)	(101,804)
Cintas Corporation
Condensed Consolidating Financial Statements
Net income	138,091	100,181
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	115	0
Change in fair value of derivatives	(12,037)
Amortization of interest rate lock agreements	385	0
Change in fair value of available-for-sale securities	(1)	0
Other comprehensive loss	(11,538)	0
Comprehensive income	126,553	100,181
Corp. 2
Condensed Consolidating Financial Statements
Net income	43,871	31,810
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	0	0
Change in fair value of derivatives	(12,037)
Amortization of interest rate lock agreements	385	488
Change in fair value of available-for-sale securities	0	0
Other comprehensive loss	(11,652)	488
Comprehensive income	32,219	32,298
Subsidiary Guarantors
Condensed Consolidating Financial Statements
Net income	87,515	67,855
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	0	0
Change in fair value of derivatives	0
Amortization of interest rate lock agreements	0	0
Change in fair value of available-for-sale securities	0	0
Other comprehensive loss	0	0
Comprehensive income	87,515	67,855
Non- Guarantors
Condensed Consolidating Financial Statements
Net income	3,879	2,139
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	115	(12,013)
Change in fair value of derivatives	0
Amortization of interest rate lock agreements	0	0
Change in fair value of available-for-sale securities	(1)	(8)
Other comprehensive loss	114	(12,021)
Comprehensive income	$ 3,993	$ (9,882)

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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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 gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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

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