Supplemental Guarantor Information - Consolidating Condensed Statements of Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
Aug. 31, 2018	Aug. 31, 2017
Condensed Consolidating Financial Statements
Net income	$ 212,515	$ 217,211
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(3,019)	35,184
Change in fair value of interest rate lock agreements	(3,168)	0
Amortization of interest rate lock agreements	(295)	(172)
Change in fair value of available-for-sale securities		20
Other comprehensive (loss) income	(6,482)	35,032
Comprehensive income	206,033	252,243
Eliminations
Condensed Consolidating Financial Statements
Net income	(210,655)	(214,406)
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	3,019	(35,184)
Change in fair value of interest rate lock agreements	3,168
Amortization of interest rate lock agreements	295	172
Change in fair value of available-for-sale securities		(20)
Other comprehensive (loss) income	6,482	(35,032)
Comprehensive income	(204,173)	(249,438)
Cintas Corporation
Condensed Consolidating Financial Statements
Net income	212,515	217,211
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(3,019)	35,184
Change in fair value of interest rate lock agreements	(3,168)
Amortization of interest rate lock agreements	(295)	(172)
Change in fair value of available-for-sale securities		20
Other comprehensive (loss) income	(6,482)	35,032
Comprehensive income	206,033	252,243
Corp. 2
Condensed Consolidating Financial Statements
Net income	62,612	118,530
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0	0
Change in fair value of interest rate lock agreements	(3,168)
Amortization of interest rate lock agreements	(295)	(172)
Change in fair value of available-for-sale securities		0
Other comprehensive (loss) income	(3,463)	(172)
Comprehensive income	59,149	118,358
Subsidiary Guarantors
Condensed Consolidating Financial Statements
Net income	143,033	87,171
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0	0
Change in fair value of interest rate lock agreements	0
Amortization of interest rate lock agreements	0	0
Change in fair value of available-for-sale securities		0
Other comprehensive (loss) income	0	0
Comprehensive income	143,033	87,171
Non- Guarantors
Condensed Consolidating Financial Statements
Net income	5,010	8,705
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(3,019)	35,184
Change in fair value of interest rate lock agreements	0
Amortization of interest rate lock agreements	0	0
Change in fair value of available-for-sale securities		20
Other comprehensive (loss) income	(3,019)	35,204
Comprehensive income	$ 1,991	$ 43,909

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