Supplemental Guarantor Information - Condensed Consolidating Statement of Cash Flows (Details) - USD ($) $ in Thousands		3 Months Ended
	Jun. 30, 2014	Aug. 31, 2015	Aug. 31, 2014
Cash flows from operating activities:
Net income		$ 100,181	$ 110,108
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation		36,165	35,448
Amortization of intangible assets		3,603	4,206
Stock-based compensation		23,917	12,280
Gain on sale of Storage Assets		(4,843)	0
Loss on investment in Shred-it Partnership		14,516	0
Gain on deconsolidation of Shredding		0	(6,619)
Gain on sale of stock of an equity method investment		0	(21,739)
Deferred income taxes		5,632	2,108
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net		(19,255)	8,222
Inventories, net		(8,109)	1,377
Uniforms and other rental items in service		(4,939)	(7,112)
Prepaid expenses and other current assets		(6,024)	(5,884)
Accounts payable		15,531	(1,325)
Accrued compensation and related liabilities		(35,579)	(41,262)
Accrued liabilities and other		(26,253)	10,384
Income taxes, current		48,540	48,009
Net cash provided by operating activities		143,083	148,201
Cash flows from investing activities:
Capital expenditures		(62,631)	(68,050)
Proceeds from redemption of marketable securities		152,907	0
Purchase of marketable securities and investments		(196,020)	(6,981)
Proceeds from sale of Storage Assets		24,395	0
Proceeds from Shredding Transaction, net of cash contributed		0	3,344
Proceeds from sale of stock of an equity method investment		0	29,933
Dividends received on equity method investment	$ 5,200	0	5,247
Acquisitions of businesses, net of cash acquired		(121,434)	(2,328)
Other, net		921	16
Net cash used in investing activities		(201,862)	(38,819)
Cash flows from financing activities:
Proceeds from issuance of debt		0
Repayment of debt		(16)	(180)
Exercise of stock-based compensation awards		11,844	13,623
Repurchase of common stock		(221,598)	(61,439)
Other, net		51	6,798
Net cash used in financing activities		(209,719)	(41,198)
Effect of exchange rate changes on cash and cash equivalents		(1,715)	(19)
Net (decrease) increase in cash and cash equivalents		(270,213)	68,165
Cash and cash equivalents at beginning of period		417,073	513,288
Cash and cash equivalents at end of period		146,860	581,453
Cintas Corporation
Cash flows from operating activities:
Net income		100,181	110,108
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation		0	0
Amortization of intangible assets		0	0
Stock-based compensation		23,917	12,280
Gain on sale of Storage Assets		0
Loss on investment in Shred-it Partnership		0
Gain on deconsolidation of Shredding			0
Gain on sale of stock of an equity method investment			0
Deferred income taxes		0	0
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net		0	0
Inventories, net		0	0
Uniforms and other rental items in service		0	0
Prepaid expenses and other current assets		0	0
Accounts payable		0	0
Accrued compensation and related liabilities		0	0
Accrued liabilities and other		0	0
Income taxes, current		0	0
Net cash provided by operating activities		124,098	122,388
Cash flows from investing activities:
Capital expenditures		0	0
Proceeds from redemption of marketable securities		0
Purchase of marketable securities and investments		0	0
Proceeds from sale of Storage Assets		0
Proceeds from Shredding Transaction, net of cash contributed			0
Proceeds from sale of stock of an equity method investment			0
Dividends received on equity method investment			0
Acquisitions of businesses, net of cash acquired		0	0
Other, net		85,656	(80,725)
Net cash used in investing activities		85,656	(80,725)
Cash flows from financing activities:
Proceeds from issuance of debt		0
Repayment of debt		0	0
Exercise of stock-based compensation awards		11,844	13,623
Repurchase of common stock		(221,598)	(61,439)
Other, net		0	6,153
Net cash used in financing activities		(209,754)	(41,663)
Effect of exchange rate changes on cash and cash equivalents		0	0
Net (decrease) increase in cash and cash equivalents		0	0
Cash and cash equivalents at beginning of period		0	0
Cash and cash equivalents at end of period		0	0
Corp. 2
Cash flows from operating activities:
Net income		27,628	33,150
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation		21,427	19,547
Amortization of intangible assets		3,513	3,773
Stock-based compensation		0	0
Gain on sale of Storage Assets		(4,843)
Loss on investment in Shred-it Partnership		13,427
Gain on deconsolidation of Shredding			(6,619)
Gain on sale of stock of an equity method investment			0
Deferred income taxes		21	0
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net		(19,744)	10,014
Inventories, net		(8,856)	(1,045)
Uniforms and other rental items in service		(3,076)	(4,450)
Prepaid expenses and other current assets		(100)	200
Accounts payable		28,715	(70,520)
Accrued compensation and related liabilities		(24,891)	(28,267)
Accrued liabilities and other		(1,775)	(31,741)
Income taxes, current		8,231	6,913
Net cash provided by operating activities		39,677	(69,045)
Cash flows from investing activities:
Capital expenditures		(29,695)	(22,686)
Proceeds from redemption of marketable securities		0
Purchase of marketable securities and investments		2,215	(1,721)
Proceeds from sale of Storage Assets		24,395
Proceeds from Shredding Transaction, net of cash contributed			3,344
Proceeds from sale of stock of an equity method investment			0
Dividends received on equity method investment			0
Acquisitions of businesses, net of cash acquired		(96,353)	(2,328)
Other, net		59,519	94,602
Net cash used in investing activities		(39,919)	71,211
Cash flows from financing activities:
Proceeds from issuance of debt		0
Repayment of debt		(309)	(450)
Exercise of stock-based compensation awards		0	0
Repurchase of common stock		0	0
Other, net		488	488
Net cash used in financing activities		179	38
Effect of exchange rate changes on cash and cash equivalents		0	0
Net (decrease) increase in cash and cash equivalents		(63)	2,204
Cash and cash equivalents at beginning of period		74,145	73,540
Cash and cash equivalents at end of period		74,082	75,744
Subsidiary Guarantors
Cash flows from operating activities:
Net income		71,643	75,016
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation		12,340	13,037
Amortization of intangible assets		40	15
Stock-based compensation		0	0
Gain on sale of Storage Assets		0
Loss on investment in Shred-it Partnership		0
Gain on deconsolidation of Shredding			0
Gain on sale of stock of an equity method investment			(21,739)
Deferred income taxes		5,784	2,083
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net		(1,038)	(3,852)
Inventories, net		(1,130)	2,430
Uniforms and other rental items in service		(586)	(1,673)
Prepaid expenses and other current assets		(5,998)	(6,288)
Accounts payable		(14,970)	71,606
Accrued compensation and related liabilities		(9,258)	(10,204)
Accrued liabilities and other		(22,975)	42,084
Income taxes, current		40,411	40,601
Net cash provided by operating activities		74,263	203,116
Cash flows from investing activities:
Capital expenditures		(29,617)	(42,239)
Proceeds from redemption of marketable securities		0
Purchase of marketable securities and investments		(10,148)	(15,260)
Proceeds from sale of Storage Assets		0
Proceeds from Shredding Transaction, net of cash contributed			0
Proceeds from sale of stock of an equity method investment			29,933
Dividends received on equity method investment			5,247
Acquisitions of businesses, net of cash acquired		0	0
Other, net		(239,160)	(114,793)
Net cash used in investing activities		(278,925)	(137,112)
Cash flows from financing activities:
Proceeds from issuance of debt		(55)
Repayment of debt		853	1,116
Exercise of stock-based compensation awards		0	0
Repurchase of common stock		0	0
Other, net		0	0
Net cash used in financing activities		798	1,116
Effect of exchange rate changes on cash and cash equivalents		0	0
Net (decrease) increase in cash and cash equivalents		(203,864)	67,120
Cash and cash equivalents at beginning of period		249,203	399,525
Cash and cash equivalents at end of period		45,339	466,645
Non- Guarantors
Cash flows from operating activities:
Net income		2,533	3,177
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation		2,398	2,864
Amortization of intangible assets		50	418
Stock-based compensation		0	0
Gain on sale of Storage Assets		0
Loss on investment in Shred-it Partnership		1,089
Gain on deconsolidation of Shredding			0
Gain on sale of stock of an equity method investment			0
Deferred income taxes		(173)	25
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net		1,527	2,060
Inventories, net		(334)	(1,174)
Uniforms and other rental items in service		(700)	(1,053)
Prepaid expenses and other current assets		74	204
Accounts payable		1,802	(2,415)
Accrued compensation and related liabilities		(1,430)	(2,791)
Accrued liabilities and other		(2,227)	(705)
Income taxes, current		(102)	495
Net cash provided by operating activities		4,507	1,105
Cash flows from investing activities:
Capital expenditures		(3,319)	(3,125)
Proceeds from redemption of marketable securities		152,907
Purchase of marketable securities and investments		(192,097)	0
Proceeds from sale of Storage Assets		0
Proceeds from Shredding Transaction, net of cash contributed			0
Proceeds from sale of stock of an equity method investment			0
Dividends received on equity method investment			0
Acquisitions of businesses, net of cash acquired		(25,081)	0
Other, net		(1,270)	823
Net cash used in investing activities		(68,860)	(2,302)
Cash flows from financing activities:
Proceeds from issuance of debt		55
Repayment of debt		164	(100)
Exercise of stock-based compensation awards		0	0
Repurchase of common stock		0	0
Other, net		(437)	157
Net cash used in financing activities		(218)	57
Effect of exchange rate changes on cash and cash equivalents		(1,715)	(19)
Net (decrease) increase in cash and cash equivalents		(66,286)	(1,159)
Cash and cash equivalents at beginning of period		93,725	40,223
Cash and cash equivalents at end of period		27,439	39,064
Eliminations
Cash flows from operating activities:
Net income		(101,804)	(111,343)
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation		0	0
Amortization of intangible assets		0	0
Stock-based compensation		0	0
Gain on sale of Storage Assets		0
Loss on investment in Shred-it Partnership		0
Gain on deconsolidation of Shredding			0
Gain on sale of stock of an equity method investment			0
Deferred income taxes		0	0
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net		0	0
Inventories, net		2,211	1,166
Uniforms and other rental items in service		(577)	64
Prepaid expenses and other current assets		0	0
Accounts payable		(16)	4
Accrued compensation and related liabilities		0	0
Accrued liabilities and other		724	746
Income taxes, current		0	0
Net cash provided by operating activities		(99,462)	(109,363)
Cash flows from investing activities:
Capital expenditures		0	0
Proceeds from redemption of marketable securities		0
Purchase of marketable securities and investments		4,010	10,000
Proceeds from sale of Storage Assets		0
Proceeds from Shredding Transaction, net of cash contributed			0
Proceeds from sale of stock of an equity method investment			0
Dividends received on equity method investment			0
Acquisitions of businesses, net of cash acquired		0	0
Other, net		96,176	100,109
Net cash used in investing activities		100,186	110,109
Cash flows from financing activities:
Proceeds from issuance of debt		0
Repayment of debt		(724)	(746)
Exercise of stock-based compensation awards		0	0
Repurchase of common stock		0	0
Other, net		0	0
Net cash used in financing activities		(724)	(746)
Effect of exchange rate changes on cash and cash equivalents		0	0
Net (decrease) increase in cash and cash equivalents		0	0
Cash and cash equivalents at beginning of period		0	0
Cash and cash equivalents at end of period		$ 0	$ 0