Supplemental Guarantor Information - Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Feb. 29, 2020	Nov. 30, 2019	Aug. 31, 2019	Feb. 28, 2019	Nov. 30, 2018	Aug. 31, 2018	Feb. 29, 2020	Feb. 28, 2019
Revenue:
Revenue	$ 1,810,648			$ 1,682,330			$ 5,465,536	$ 5,098,573
Equity in net income of affiliates	0			0			0	0
Total revenue	1,810,648			1,682,330			5,465,536	5,098,573
Costs and expenses (income):
Selling and administrative expenses	509,743			476,099			1,570,666	1,472,404
G&K Services, Inc. integration expenses	0			799			0	13,496
Operating income	314,652			278,255			955,262	819,123
Gain on sale of a cost method investment	0			0			0	69,373
Interest income	(347)			(70)			(792)	(957)
Interest expense (income)	25,943			26,770			79,441	75,954
Income before income taxes	289,056			251,555			876,613	813,499
Income taxes	54,536			50,632			144,838	157,035
Income from continuing operations	234,520			200,923			731,775	656,464
Income (loss) from discontinued operations, net of tax	0			2,411			(323)	2,398
Net income	234,520	$ 246,120	$ 250,812	203,334	$ 243,013	$ 212,515	731,452	658,862
Eliminations
Revenue:
Equity in net income of affiliates	(234,520)			(200,923)			(731,775)	(656,464)
Total revenue	(473,917)			(429,160)			(1,479,317)	(1,372,971)
Costs and expenses (income):
Selling and administrative expenses	(7,706)			(8,156)			(21,382)	(26,721)
G&K Services, Inc. integration expenses				0				0
Operating income	(234,654)			(196,929)			(745,047)	(648,118)
Gain on sale of a cost method investment								0
Interest income	1			3			4	5
Interest expense (income)	0			0			0	0
Income before income taxes	(234,655)			(196,932)			(745,051)	(648,123)
Income taxes	(25)			(19)			(86)	(77)
Income from continuing operations				(196,913)			(744,965)	(648,046)
Income (loss) from discontinued operations, net of tax				(2,411)			323	(2,398)
Net income	(234,630)			(199,324)			(744,642)	(650,444)
Cintas Corporation | Reportable Legal Entities
Revenue:
Equity in net income of affiliates	234,520			200,923			731,775	656,464
Total revenue	234,520			200,923			731,775	656,464
Costs and expenses (income):
Selling and administrative expenses	0			0			0	0
G&K Services, Inc. integration expenses				0				0
Operating income	234,520			200,923			731,775	656,464
Gain on sale of a cost method investment								0
Interest income	0			0			0	0
Interest expense (income)	0			0			0	0
Income before income taxes	234,520			200,923			731,775	656,464
Income taxes	0			0			0	0
Income from continuing operations				200,923			731,775	656,464
Income (loss) from discontinued operations, net of tax				2,411			(323)	2,398
Net income	234,520			203,334			731,452	658,862
Corp. 2 | Reportable Legal Entities
Revenue:
Equity in net income of affiliates	0			0			0	0
Total revenue	1,729,730			1,611,888			5,246,097	4,898,506
Costs and expenses (income):
Selling and administrative expenses	576,433			527,720			1,767,258	1,608,906
G&K Services, Inc. integration expenses				(141)				8,508
Operating income	109,827			98,974			346,993	294,060
Gain on sale of a cost method investment								0
Interest income	(131)			(56)			(438)	(559)
Interest expense (income)	26,033			26,872			79,657	76,579
Income before income taxes	83,925			72,158			267,774	218,040
Income taxes	15,717			12,330			42,578	42,159
Income from continuing operations				59,828			225,196	175,881
Income (loss) from discontinued operations, net of tax				2,411			(323)	2,398
Net income	68,208			62,239			224,873	178,279
Subsidiary Guarantors | Reportable Legal Entities
Revenue:
Equity in net income of affiliates	0			0			0	0
Total revenue	189,397			176,831			574,868	542,963
Costs and expenses (income):
Selling and administrative expenses	(94,155)			(74,507)			(277,575)	(207,745)
G&K Services, Inc. integration expenses				(379)				2,754
Operating income	196,494			166,425			590,685	490,719
Gain on sale of a cost method investment								69,373
Interest income	(195)			1			(302)	(364)
Interest expense (income)	(91)			(104)			(231)	(639)
Income before income taxes	196,780			166,528			591,218	561,095
Income taxes	36,380			35,665			94,010	107,497
Income from continuing operations				130,863			497,208	453,598
Income (loss) from discontinued operations, net of tax				0			0	0
Net income	160,400			130,863			497,208	453,598
Non- Guarantors | Reportable Legal Entities
Revenue:
Equity in net income of affiliates	0			0			0	0
Total revenue	130,918			121,848			392,113	373,611
Costs and expenses (income):
Selling and administrative expenses	35,171			31,042			102,365	97,964
G&K Services, Inc. integration expenses				1,319				2,234
Operating income	8,465			8,862			30,856	25,998
Gain on sale of a cost method investment								0
Interest income	(22)			(18)			(56)	(39)
Interest expense (income)	1			2			15	14
Income before income taxes	8,486			8,878			30,897	26,023
Income taxes	2,464			2,656			8,336	7,456
Income from continuing operations				6,222			22,561	18,567
Income (loss) from discontinued operations, net of tax				0			0	0
Net income	6,022			6,222			22,561	18,567
Uniform Rental and Facility Services
Revenue:
Revenue	1,448,021			1,358,322			4,372,524	4,124,038
Cost of revenue	784,930			748,971			2,338,543	2,256,543
Uniform Rental and Facility Services | Eliminations
Revenue:
Revenue	(691)			(10,925)			(1,831)	(86,008)
Cost of revenue	(32,852)			(39,275)			(95,551)	(166,737)
Uniform Rental and Facility Services | Cintas Corporation | Reportable Legal Entities
Revenue:
Revenue	0			0			0	0
Cost of revenue	0			0			0	0
Uniform Rental and Facility Services | Corp. 2 | Reportable Legal Entities
Revenue:
Revenue	1,150,780			1,092,594			3,477,631	3,365,841
Cost of revenue	634,638			612,167			1,891,754	1,896,767
Uniform Rental and Facility Services | Subsidiary Guarantors | Reportable Legal Entities
Revenue:
Revenue	189,333			176,787			574,536	542,826
Cost of revenue	112,865			111,103			337,104	332,208
Uniform Rental and Facility Services | Non- Guarantors | Reportable Legal Entities
Revenue:
Revenue	108,599			99,866			322,188	301,379
Cost of revenue	70,279			64,976			205,236	194,305
Other
Revenue:
Revenue	362,627			324,008			1,093,012	974,535
Cost of revenue	201,323			178,206			601,065	537,007
Other | Eliminations
Revenue:
Revenue	(238,706)			(217,312)			(745,711)	(630,499)
Cost of revenue	(198,705)			(184,800)			(617,337)	(531,395)
Other | Cintas Corporation | Reportable Legal Entities
Revenue:
Revenue	0			0			0	0
Cost of revenue	0			0			0	0
Other | Corp. 2 | Reportable Legal Entities
Revenue:
Revenue	578,950			519,294			1,768,466	1,532,665
Cost of revenue	408,832			373,168			1,240,092	1,090,265
Other | Subsidiary Guarantors | Reportable Legal Entities
Revenue:
Revenue	64			44			332	137
Cost of revenue	(25,807)			(25,811)			(75,346)	(74,973)
Other | Non- Guarantors | Reportable Legal Entities
Revenue:
Revenue	22,319			21,982			69,925	72,232
Cost of revenue	$ 17,003			$ 15,649			$ 53,656	$ 53,110