Supplemental Guarantor Information - Condensed Consolidating Statement of Cash Flows (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jun. 30, 2014	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014
Cash flows from operating activities:
Net income		$ 345,100	$ 120,412	$ 445,281	$ 230,520
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation				73,130	70,451
Amortization of intangible assets				7,764	7,702
Stock-based compensation				40,241	24,785
Gain on Storage Transactions				(15,786)	(34,137)
(Gain) loss on sale of investment in Shred-it Partnership				(374,026)	0
Loss on investment in Shred-it Partnership				24,288	(6,619)
Gain on sale of stock of an equity method investment		0	0	0	(21,739)
Deferred income taxes				(98,423)	10,346
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net				(39,418)	(12,747)
Inventories, net				(19,841)	14,847
Uniforms and other rental items in service				(10,893)	(23,473)
Prepaid expenses and other current assets				(2,369)	(2,622)
Accounts payable				19,368	27,982
Accrued compensation and related liabilities				(22,771)	(25,111)
Accrued liabilities and other				1,041	24,780
Income taxes, current				237,451	7,608
Net cash provided by operating activities				265,037	292,573
Cash flows from investing activities:
Capital expenditures				(121,817)	(113,025)
Proceeds from redemption of marketable securities				212,081	0
Purchase of marketable securities and investments				(271,341)	(11,978)
Proceeds from Storage Transactions, net of cash contributed				35,338	153,996
Proceeds from Shredding Transaction				0	3,344
Proceeds from sale of investment in Shred-it Partnership		578,257		578,257	0
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				(121,237)	(3,015)
Other, net				1,987	1,681
Net cash provided by investing activities				313,268	66,183
Cash flows from financing activities:
Proceeds from issuance of debt				0
Repayment of debt				(16)	(364)
Exercise of stock-based compensation awards				17,444	22,472
Repurchase of common stock				(402,293)	(63,573)
Other, net				646	1,758
Net cash used in financing activities				(384,219)	(39,707)
Effect of exchange rate changes on cash and cash equivalents				(4,374)	(5,613)
Net increase in cash and cash equivalents				189,712	313,436
Cash and cash equivalents at beginning of period				417,073	513,288
Cash and cash equivalents at end of period		606,785	826,724	606,785	826,724
Cintas Corporation
Cash flows from operating activities:
Net income		345,100	120,412	445,281	230,520
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				40,241	24,785
Gain on Storage Transactions				0	0
(Gain) loss on sale of investment in Shred-it Partnership				0
Loss on investment in Shred-it Partnership				0	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				485,522	255,305
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 Storage Transactions, net of cash contributed				0	0
Proceeds from Shredding Transaction					0
Proceeds from sale of investment in Shred-it Partnership				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				(100,673)	(214,210)
Net cash provided by investing activities				(100,673)	(214,210)
Cash flows from financing activities:
Proceeds from issuance of debt				0
Repayment of debt				0	0
Exercise of stock-based compensation awards				17,444	22,478
Repurchase of common stock				(402,293)	(63,573)
Other, net				0	0
Net cash used in financing activities				(384,849)	(41,095)
Effect of exchange rate changes on cash and cash equivalents				0	0
Net 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	0	0
Corp. 2
Cash flows from operating activities:
Net income		267,111	46,334	294,739	79,484
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation				43,675	38,814
Amortization of intangible assets				7,248	7,251
Stock-based compensation				0	0
Gain on Storage Transactions				(12,547)	(31,113)
(Gain) loss on sale of investment in Shred-it Partnership				(384,707)
Loss on investment in Shred-it Partnership				22,470	(6,619)
Gain on sale of stock of an equity method investment					0
Deferred income taxes				(93,097)	26
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net				(24,235)	(6,468)
Inventories, net				(20,022)	10,737
Uniforms and other rental items in service				(9,457)	(17,000)
Prepaid expenses and other current assets				187	327
Accounts payable				(383,328)	(144,224)
Accrued compensation and related liabilities				(17,572)	(16,742)
Accrued liabilities and other				995	(8,174)
Income taxes, current				229,909	11,945
Net cash provided by operating activities				(345,742)	(81,756)
Cash flows from investing activities:
Capital expenditures				(61,196)	(49,870)
Proceeds from redemption of marketable securities				0
Purchase of marketable securities and investments				(3,437)	(2,020)
Proceeds from Storage Transactions, net of cash contributed				32,099	93,387
Proceeds from Shredding Transaction					3,344
Proceeds from sale of investment in Shred-it Partnership				565,643
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				(96,465)	(3,015)
Other, net				(57,883)	44,502
Net cash provided by investing activities				378,761	86,328
Cash flows from financing activities:
Proceeds from issuance of debt				0
Repayment of debt				(309)	(634)
Exercise of stock-based compensation awards				0	0
Repurchase of common stock				0	0
Other, net				976	976
Net cash used in financing activities				667	342
Effect of exchange rate changes on cash and cash equivalents				0	0
Net increase in cash and cash equivalents				33,686	4,914
Cash and cash equivalents at beginning of period				74,145	73,540
Cash and cash equivalents at end of period		107,831	78,454	107,831	78,454
Subsidiary Guarantors
Cash flows from operating activities:
Net income		79,931	68,745	151,574	143,761
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation				24,787	25,972
Amortization of intangible assets				337	27
Stock-based compensation				0	0
Gain on Storage Transactions				0	0
(Gain) loss on sale of investment in Shred-it Partnership				0
Loss on investment in Shred-it Partnership				0	0
Gain on sale of stock of an equity method investment					(21,739)
Deferred income taxes				(6,913)	9,073
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net				(13,603)	(8,938)
Inventories, net				(2,048)	3,258
Uniforms and other rental items in service				287	(5,155)
Prepaid expenses and other current assets				(2,593)	(2,943)
Accounts payable				397,834	171,596
Accrued compensation and related liabilities				(4,517)	(6,148)
Accrued liabilities and other				666	28,401
Income taxes, current				7,442	(3,814)
Net cash provided by operating activities				553,253	333,351
Cash flows from investing activities:
Capital expenditures				(53,804)	(57,388)
Proceeds from redemption of marketable securities				0
Purchase of marketable securities and investments				(7,549)	55,053
Proceeds from Storage Transactions, net of cash contributed				0	0
Proceeds from Shredding Transaction					0
Proceeds from sale of investment in Shred-it Partnership				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				(277,201)	(126,280)
Net cash provided by investing activities				(338,554)	(93,435)
Cash flows from financing activities:
Proceeds from issuance of debt				(55)
Repayment of debt				1,053	1,114
Exercise of stock-based compensation awards				0	0
Repurchase of common stock				0	0
Other, net				0	0
Net cash used in financing activities				998	1,114
Effect of exchange rate changes on cash and cash equivalents				0	0
Net increase in cash and cash equivalents				215,697	241,030
Cash and cash equivalents at beginning of period				249,203	399,525
Cash and cash equivalents at end of period		464,900	640,555	464,900	640,555
Non- Guarantors
Cash flows from operating activities:
Net income		(1,169)	6,637	1,364	9,814
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation				4,668	5,665
Amortization of intangible assets				179	424
Stock-based compensation				0	0
Gain on Storage Transactions				(3,239)	(3,024)
(Gain) loss on sale of investment in Shred-it Partnership				10,681
Loss on investment in Shred-it Partnership				1,818	0
Gain on sale of stock of an equity method investment					0
Deferred income taxes				1,587	1,247
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net				(1,580)	2,659
Inventories, net				(365)	(898)
Uniforms and other rental items in service				(1,530)	(2,101)
Prepaid expenses and other current assets				37	(6)
Accounts payable				4,872	605
Accrued compensation and related liabilities				(682)	(2,221)
Accrued liabilities and other				(1,344)	3,807
Income taxes, current				100	(523)
Net cash provided by operating activities				16,566	15,448
Cash flows from investing activities:
Capital expenditures				(6,817)	(5,767)
Proceeds from redemption of marketable securities				212,081
Purchase of marketable securities and investments				(264,365)	0
Proceeds from Storage Transactions, net of cash contributed				3,239	60,609
Proceeds from Shredding Transaction					0
Proceeds from sale of investment in Shred-it Partnership				12,614
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				(24,772)	0
Other, net				(3,532)	2,137
Net cash provided by investing activities				(71,552)	56,979
Cash flows from financing activities:
Proceeds from issuance of debt				55
Repayment of debt				(36)	(98)
Exercise of stock-based compensation awards				0	(6)
Repurchase of common stock				0	0
Other, net				(330)	782
Net cash used in financing activities				(311)	678
Effect of exchange rate changes on cash and cash equivalents				(4,374)	(5,613)
Net increase in cash and cash equivalents				(59,671)	67,492
Cash and cash equivalents at beginning of period				93,725	40,223
Cash and cash equivalents at end of period		34,054	107,715	34,054	107,715
Eliminations
Cash flows from operating activities:
Net income		(345,873)	(121,716)	(447,677)	(233,059)
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 Storage Transactions				0	0
(Gain) loss on sale of investment in Shred-it Partnership				0
Loss on investment in Shred-it Partnership				0	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				2,594	1,750
Uniforms and other rental items in service				(193)	783
Prepaid expenses and other current assets				0	0
Accounts payable				(10)	5
Accrued compensation and related liabilities				0	0
Accrued liabilities and other				724	746
Income taxes, current				0	0
Net cash provided by operating activities				(444,562)	(229,775)
Cash flows from investing activities:
Capital expenditures				0	0
Proceeds from redemption of marketable securities				0
Purchase of marketable securities and investments				4,010	(65,011)
Proceeds from Storage Transactions, net of cash contributed				0	0
Proceeds from Shredding Transaction					0
Proceeds from sale of investment in Shred-it Partnership				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				441,276	295,532
Net cash provided by investing activities				445,286	230,521
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 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	$ 0	$ 0