Supplemental Guarantor Information - Consolidating Condensed Statements of Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2017	Aug. 31, 2017	Nov. 30, 2016	Aug. 31, 2016	Nov. 30, 2017	Nov. 30, 2016
Condensed Consolidating Financial Statements
Net income	$ 137,109		$ 140,377		$ 354,320	$ 278,468
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(11,374)		(7,650)		23,810	(7,535)
Change in fair value of cash flow hedges	0		26,390		0	14,353
Amortization of interest rate lock agreements	(172)		385		(344)	770
Change in fair value of available-for-sale securities	(20)		1		0	0
Other comprehensive (loss) income	(11,566)	$ 35,032	19,126	$ (11,538)	23,466	7,588
Comprehensive income	125,543		159,503		377,786	286,056
Eliminations
Condensed Consolidating Financial Statements
Net income	(138,010)		(140,059)		(352,416)	(275,324)
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	11,374		7,650		(23,810)	7,535
Change in fair value of cash flow hedges			(26,390)			(14,353)
Amortization of interest rate lock agreements	172		(385)		344	(770)
Change in fair value of available-for-sale securities	20		(1)
Other comprehensive (loss) income	11,566		(19,126)		(23,466)	(7,588)
Comprehensive income	(126,444)		(159,185)		(375,882)	(282,912)
Cintas Corporation
Condensed Consolidating Financial Statements
Net income	137,109		140,377		354,320	278,468
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(11,374)		(7,650)		23,810	(7,535)
Change in fair value of cash flow hedges			26,390			14,353
Amortization of interest rate lock agreements	(172)		385		(344)	770
Change in fair value of available-for-sale securities	(20)		1
Other comprehensive (loss) income	(11,566)		19,126		23,466	7,588
Comprehensive income	125,543		159,503		377,786	286,056
Corp. 2
Condensed Consolidating Financial Statements
Net income	17,981		55,004		136,511	98,875
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0		0		0	0
Change in fair value of cash flow hedges			26,390			14,353
Amortization of interest rate lock agreements	(172)		385		(344)	770
Change in fair value of available-for-sale securities	0		0
Other comprehensive (loss) income	(172)		26,775		(344)	15,123
Comprehensive income	17,809		81,779		136,167	113,998
Subsidiary Guarantors
Condensed Consolidating Financial Statements
Net income	112,155		79,185		199,326	166,700
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0		0		0	0
Change in fair value of cash flow hedges			0			0
Amortization of interest rate lock agreements	0		0		0	0
Change in fair value of available-for-sale securities	0		0
Other comprehensive (loss) income	0		0		0	0
Comprehensive income	112,155		79,185		199,326	166,700
Non- Guarantors
Condensed Consolidating Financial Statements
Net income	7,874		5,870		16,579	9,749
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(11,374)		(7,650)		23,810	(7,535)
Change in fair value of cash flow hedges			0			0
Amortization of interest rate lock agreements	0		0		0	0
Change in fair value of available-for-sale securities	(20)		1
Other comprehensive (loss) income	(11,394)		(7,649)		23,810	(7,535)
Comprehensive income	$ (3,520)		$ (1,779)		$ 40,389	$ 2,214

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 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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