Supplemental Guarantor Information - Condensed Consolidating Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	May 31, 2018	Feb. 28, 2018	Nov. 30, 2017	Aug. 31, 2017	May 31, 2017	Feb. 28, 2017	Nov. 30, 2016	Aug. 31, 2016	May 31, 2018	May 31, 2017	May 31, 2016
Revenue:
Uniform rental and facility services									$ 5,247,124	$ 4,202,490	$ 3,759,524
Other									1,229,508	1,120,891	1,036,248
Equity in net income of affiliates									0	0	0
Total revenue	$ 1,669,550	$ 1,589,138	$ 1,606,441	$ 1,611,503	$ 1,530,287	$ 1,255,367	$ 1,271,077	$ 1,266,650	6,476,632	5,323,381	4,795,772
Costs and expenses (income):
Cost of uniform rental and facility services									2,886,959	2,307,774	2,092,833
Cost of other									681,150	635,312	601,599
Selling and administrative expenses									1,916,792	1,527,380	1,332,399
G&K Services, Inc. transaction and integration expenses									41,897	79,224	0
Operating income									949,834	773,691	768,941
Interest income									(1,342)	(237)	(896)
Interest expense (income)									110,175	86,524	64,522
Income before income taxes									841,001	687,404	705,315
Income taxes									57,069	230,118	256,710
Income from continuing operations	$ 189,298	$ 295,789	$ 137,737	$ 161,108	$ 82,174	$ 116,954	$ 121,950	$ 136,208	783,932	457,286	448,605
Income from discontinued operations, net of tax									58,654	23,422	244,915
Net income									842,586	480,708	693,520
Eliminations
Revenue:
Uniform rental and facility services									(197,230)	(170,960)	(155,260)
Other									(637,541)	(558,802)	(523,118)
Equity in net income of affiliates									(783,932)	(457,286)	(448,605)
Total revenue									(1,618,703)	(1,187,048)	(1,126,983)
Costs and expenses (income):
Cost of uniform rental and facility services									(298,335)	(256,964)	(236,103)
Cost of other									(507,034)	(450,169)	(407,775)
Selling and administrative expenses									(31,186)	(25,614)	(27,075)
G&K Services, Inc. transaction and integration expenses									0	0
Operating income									(782,148)	(454,301)	(456,030)
Interest income									3	2	2
Interest expense (income)									0	0	0
Income before income taxes									(782,151)	(454,303)	(456,032)
Income taxes									(122)	(101)	(116)
Income from continuing operations									(782,029)	(454,202)	(455,916)
Income from discontinued operations, net of tax									(58,605)	(23,422)	(244,788)
Net income									(840,634)	(477,624)	(700,704)
Corporate
Revenue:
Total revenue									0	0	0
Costs and expenses (income):
Selling and administrative expenses									0	0	0
Income before income taxes									(108,833)	(86,287)	(63,626)
Cintas Corporation | Corporate
Revenue:
Uniform rental and facility services									0	0	0
Other									0	0	0
Equity in net income of affiliates									783,932	457,286	448,605
Total revenue									783,932	457,286	448,605
Costs and expenses (income):
Cost of uniform rental and facility services									0	0	0
Cost of other									0	0	0
Selling and administrative expenses									0	0	0
G&K Services, Inc. transaction and integration expenses									0	0
Operating income									783,932	457,286	448,605
Interest income									0	0	0
Interest expense (income)									0	0	0
Income before income taxes									783,932	457,286	448,605
Income taxes									0	0	0
Income from continuing operations									783,932	457,286	448,605
Income from discontinued operations, net of tax									58,654	23,422	244,915
Net income									842,586	480,708	693,520
Corp. 2 | Corporate
Revenue:
Uniform rental and facility services									4,361,716	3,511,483	3,147,844
Other									1,778,845	1,604,877	1,484,556
Equity in net income of affiliates									0	0	0
Total revenue									6,140,561	5,116,360	4,632,400
Costs and expenses (income):
Cost of uniform rental and facility services									2,511,854	2,021,365	1,835,835
Cost of other									1,183,036	1,070,780	1,001,576
Selling and administrative expenses									2,093,655	1,686,209	1,497,106
G&K Services, Inc. transaction and integration expenses									15,383	51,868
Operating income									336,633	286,138	297,883
Interest income									(310)	(26)	0
Interest expense (income)									111,292	89,706	65,534
Income before income taxes									225,651	196,458	232,349
Income taxes									(48,907)	65,829	82,783
Income from continuing operations									274,558	130,629	149,566
Income from discontinued operations, net of tax									68,293	22,287	250,625
Net income									342,851	152,916	400,191
Subsidiary Guarantors | Corporate
Revenue:
Uniform rental and facility services									681,846	604,679	553,414
Other									112	1,810	8,540
Equity in net income of affiliates									0	0	0
Total revenue									681,958	606,489	561,954
Costs and expenses (income):
Cost of uniform rental and facility services									418,722	378,404	350,500
Cost of other									(57,220)	(41,509)	(40,741)
Selling and administrative expenses									(271,222)	(220,887)	(206,889)
G&K Services, Inc. transaction and integration expenses									22,148	19,060
Operating income									569,530	471,421	459,084
Interest income									(242)	(191)	(666)
Interest expense (income)									(1,017)	(2,978)	(1,027)
Income before income taxes									570,789	474,590	460,777
Income taxes									90,886	159,025	164,169
Income from continuing operations									479,903	315,565	296,608
Income from discontinued operations, net of tax									(9,688)	0	0
Net income									470,215	315,565	296,608
Non- Guarantors | Corporate
Revenue:
Uniform rental and facility services									400,792	257,288	213,526
Other									88,092	73,006	66,270
Equity in net income of affiliates									0	0	0
Total revenue									488,884	330,294	279,796
Costs and expenses (income):
Cost of uniform rental and facility services									254,718	164,969	142,601
Cost of other									62,368	56,210	48,539
Selling and administrative expenses									125,545	87,672	69,257
G&K Services, Inc. transaction and integration expenses									4,366	8,296
Operating income									41,887	13,147	19,399
Interest income									(793)	(22)	(232)
Interest expense (income)									(100)	(204)	15
Income before income taxes									42,780	13,373	19,616
Income taxes									15,212	5,365	9,874
Income from continuing operations									27,568	8,008	9,742
Income from discontinued operations, net of tax									0	1,135	(5,837)
Net income									$ 27,568	$ 9,143	$ 3,905