Supplemental Guarantor Information (Condensed Consolidated Statements of Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	May 31, 2013	Feb. 28, 2013	Nov. 30, 2012	Aug. 31, 2012	May 31, 2012	Feb. 29, 2012	Nov. 30, 2011	Aug. 31, 2011	May 31, 2013		May 31, 2012		May 31, 2011
Condensed Consolidating Financial Statements
Net income	$ 85,977	$ 74,705	$ 78,027	$ 76,733	$ 78,614	$ 76,035	$ 74,350	$ 68,638	$ 315,442		$ 297,637		$ 246,989
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments									(1,087)		(17,815)		27,344
Change in fair value of derivatives									(187)	[1]	(5,286)	[1]	(6,096)	[1]
Amortization of interest rate lock agreements									1,952		1,508		767
Change in fair value of available-for-sale securities									14	[2]	24	[2]	3	[2]
Other									768	[3]	(575)	[3]	656	[3]
Other comprehensive income (loss)									1,460		(22,144)		22,674
Comprehensive income									316,902		275,493		269,663
Cintas Corporation [Member]
Condensed Consolidating Financial Statements
Net income									315,442		297,637		246,989
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments									0		0		0
Change in fair value of derivatives									0		0		0
Amortization of interest rate lock agreements									0		0		0
Change in fair value of available-for-sale securities									0		0		0
Other									0		0		0
Other comprehensive income (loss)									0		0		0
Comprehensive income									315,442		297,637		246,989
Corp. 2 [Member]
Condensed Consolidating Financial Statements
Net income									98,748		165,559		105,914
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments									(12)		(18)		110
Change in fair value of derivatives									(187)		(5,604)		(5,814)
Amortization of interest rate lock agreements									1,952		1,508		767
Change in fair value of available-for-sale securities									0		0		(22)
Other									0		0		0
Other comprehensive income (loss)									1,753		(4,114)		(4,959)
Comprehensive income									100,501		161,445		100,955
Subsidiary Guarantors [Member]
Condensed Consolidating Financial Statements
Net income									216,727		230,677		134,424
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments									0		0		0
Change in fair value of derivatives									0		0		0
Amortization of interest rate lock agreements									0		0		0
Change in fair value of available-for-sale securities									14		0		0
Other									768		(575)		656
Other comprehensive income (loss)									782		(575)		656
Comprehensive income									217,509		230,102		135,080
Non-Guarantors [Member]
Condensed Consolidating Financial Statements
Net income									32,793		437,579		103,964
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments									(1,075)		(17,797)		27,234
Change in fair value of derivatives									0		318		(282)
Amortization of interest rate lock agreements									0		0		0
Change in fair value of available-for-sale securities									0		24		25
Other									0		0		0
Other comprehensive income (loss)									(1,075)		(17,455)		26,977
Comprehensive income									31,718		420,124		130,941
Eliminations [Member]
Condensed Consolidating Financial Statements
Net income									(348,268)		(833,815)		(344,302)
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments									0		0		0
Change in fair value of derivatives									0		0		0
Amortization of interest rate lock agreements									0		0		0
Change in fair value of available-for-sale securities									0		0		0
Other									0		0		0
Other comprehensive income (loss)									0		0		0
Comprehensive income									$ (348,268)		$ (833,815)		$ (344,302)

[1] Net of less than $0.1 million, $3.1 million and $3.8 million of tax expense for the fiscal years ended May 31, 2013, 2012 and 2011, respectively.

[2] Net of less than $0.1 million of tax benefit for each of the fiscal years ended May 31, 2013, 2012 and 2011, respectively.

[3] Net of $0.3 million of tax benefit, $0.2 million of tax expense and $0.2 million of tax benefit for the fiscal years ended May 31, 2013, 2012 and 2011, respectively.