Supplemental Guarantor Information - Condensed Consolidating Statement of Cash Flows (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
	Jun. 30, 2014	Feb. 29, 2016	Nov. 30, 2015	Feb. 28, 2015	Feb. 29, 2016	Feb. 28, 2015
Cash flows from operating activities:
Net income		$ 117,341		$ 94,883	$ 562,622	$ 325,403
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation					110,535	104,950
Amortization of intangible assets					12,136	11,090
Stock-based compensation					57,169	36,016
Gain on Storage Transactions					(15,786)	(35,036)
Loss on investment in Shred-it Partnership					24,288	4,570
(Gain) loss on sale of investment in Shred-it Partnership					(374,026)	0
Gain on sale of stock of an equity method investment		0		0	0	(21,739)
Deferred income taxes					(74,540)	15,428
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net					(41,523)	(3,168)
Inventories, net					(24,009)	15,370
Uniforms and other rental items in service					(6,905)	(22,203)
Prepaid expenses and other current assets					(1,580)	(1,609)
Accounts payable					37,370	(33,615)
Accrued compensation and related liabilities					(3,731)	(7,086)
Accrued liabilities and other					(18,301)	1,841
Income taxes, current					53,435	(12,566)
Net cash provided by operating activities					297,154	377,646
Cash flows from investing activities:
Capital expenditures					(207,502)	(163,040)
Proceeds from redemption of marketable securities					327,779	18,711
Purchase of marketable securities and investments					(384,796)	(79,947)
Proceeds from Storage Transactions, net of cash contributed					35,338	154,891
Proceeds from Shredding Transactions			$ 578,300		578,257	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					(151,731)	(13,798)
Other, net					4,433	1,583
Net cash provided by (used in) investing activities					201,778	(43,076)
Cash flows from financing activities:
Proceeds from issuance of debt					0	0
Repayment of debt					(16)	(456)
Exercise of stock-based compensation awards					22,260	31,956
Dividends paid					(115,273)	(201,941)
Repurchase of common stock					(502,439)	(314,648)
Other, net					1,153	3,139
Net cash used in financing activities					(594,315)	(481,950)
Effect of exchange rate changes on cash and cash equivalents					(6,574)	(7,588)
Net decrease in cash and cash equivalents					(101,957)	(154,968)
Cash and cash equivalents at beginning of period					417,073	513,288
Cash and cash equivalents at end of period		315,116		358,320	315,116	358,320
Cintas Corporation
Cash flows from operating activities:
Net income		117,341		94,883	562,622	325,403
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					57,169	36,016
Gain on Storage Transactions					0	0
Loss on investment in Shred-it Partnership					0	0
(Gain) loss on sale of investment in Shred-it Partnership					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					619,791	361,419
Cash flows from investing activities:
Capital expenditures					0	0
Proceeds from redemption of marketable securities					0	0
Purchase of marketable securities and investments					0	0
Proceeds from Storage Transactions, net of cash contributed					0	0
Proceeds from Shredding Transactions					0	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					(24,380)	123,154
Net cash provided by (used in) investing activities					(24,380)	123,154
Cash flows from financing activities:
Proceeds from issuance of debt					0	0
Repayment of debt					0	0
Exercise of stock-based compensation awards					22,260	31,956
Dividends paid					(115,232)	(201,881)
Repurchase of common stock					(502,439)	(314,648)
Other, net					0	0
Net cash used in financing activities					(595,411)	(484,573)
Effect of exchange rate changes on cash and cash equivalents					0	0
Net decrease 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		37,682		23,449	332,421	102,933
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation					66,555	58,898
Amortization of intangible assets					11,612	10,620
Stock-based compensation					0	0
Gain on Storage Transactions					(12,547)	(31,113)
Loss on investment in Shred-it Partnership					22,470	3,730
(Gain) loss on sale of investment in Shred-it Partnership					(384,707)
Gain on sale of stock of an equity method investment						0
Deferred income taxes					(82,115)	69
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net					(29,503)	2,345
Inventories, net					(25,170)	10,048
Uniforms and other rental items in service					(7,378)	(15,228)
Prepaid expenses and other current assets					68	34
Accounts payable					(339,163)	(174,010)
Accrued compensation and related liabilities					(1,850)	(3,903)
Accrued liabilities and other					(20,292)	(28,349)
Income taxes, current					53,923	15,041
Net cash provided by operating activities					(415,676)	(48,885)
Cash flows from investing activities:
Capital expenditures					(111,219)	(72,623)
Proceeds from redemption of marketable securities					0	0
Purchase of marketable securities and investments					(3,838)	(2,436)
Proceeds from Storage Transactions, net of cash contributed					32,099	93,387
Proceeds from Shredding Transactions					565,643	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					(127,524)	(13,798)
Other, net					114,598	45,096
Net cash provided by (used in) investing activities					469,759	52,970
Cash flows from financing activities:
Proceeds from issuance of debt					0	0
Repayment of debt					(309)	(726)
Exercise of stock-based compensation awards					0	0
Dividends paid					0	0
Repurchase of common stock					0	0
Other, net					1,464	1,464
Net cash used in financing activities					1,155	738
Effect of exchange rate changes on cash and cash equivalents					0	0
Net decrease in cash and cash equivalents					55,238	4,823
Cash and cash equivalents at beginning of period					74,145	73,540
Cash and cash equivalents at end of period		129,383		78,363	129,383	78,363
Subsidiary Guarantors
Cash flows from operating activities:
Net income		79,673		66,442	231,247	210,203
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation					37,094	38,081
Amortization of intangible assets					218	45
Stock-based compensation					0	0
Gain on Storage Transactions					0	86
Loss on investment in Shred-it Partnership					0	(206)
(Gain) loss on sale of investment in Shred-it Partnership					0
Gain on sale of stock of an equity method investment						(21,739)
Deferred income taxes					5,895	14,639
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net					(11,703)	(8,184)
Inventories, net					(1,583)	4,361
Uniforms and other rental items in service					3,163	(4,420)
Prepaid expenses and other current assets					(1,743)	(1,460)
Accounts payable					366,402	137,440
Accrued compensation and related liabilities					(1,641)	(1,216)
Accrued liabilities and other					2,778	25,082
Income taxes, current					(356)	(26,508)
Net cash provided by operating activities					629,771	366,204
Cash flows from investing activities:
Capital expenditures					(85,885)	(81,881)
Proceeds from redemption of marketable securities					0	0
Purchase of marketable securities and investments					(2,235)	47,169
Proceeds from Storage Transactions, net of cash contributed					0	(89)
Proceeds from Shredding Transactions					0	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					(638,714)	(545,939)
Net cash provided by (used in) investing activities					(726,834)	(545,560)
Cash flows from financing activities:
Proceeds from issuance of debt					(55)	(2,225)
Repayment of debt					1,053	3,421
Exercise of stock-based compensation awards					0	0
Dividends paid					0	0
Repurchase of common stock					0	0
Other, net					0	0
Net cash used in financing activities					998	1,196
Effect of exchange rate changes on cash and cash equivalents					0	0
Net decrease in cash and cash equivalents					(96,065)	(178,160)
Cash and cash equivalents at beginning of period					249,203	399,525
Cash and cash equivalents at end of period		153,138		221,365	153,138	221,365
Non- Guarantors
Cash flows from operating activities:
Net income		1,707		4,265	3,071	14,079
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Depreciation					6,886	7,971
Amortization of intangible assets					306	425
Stock-based compensation					0	0
Gain on Storage Transactions					(3,239)	(4,009)
Loss on investment in Shred-it Partnership					1,818	1,046
(Gain) loss on sale of investment in Shred-it Partnership					10,681
Gain on sale of stock of an equity method investment						0
Deferred income taxes					1,680	720
Change in current assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net					(317)	2,671
Inventories, net					(1,946)	(1,237)
Uniforms and other rental items in service					(2,118)	(2,161)
Prepaid expenses and other current assets					95	(183)
Accounts payable					10,132	2,949
Accrued compensation and related liabilities					(240)	(1,967)
Accrued liabilities and other					(1,511)	4,362
Income taxes, current					(132)	(1,099)
Net cash provided by operating activities					25,166	23,567
Cash flows from investing activities:
Capital expenditures					(10,398)	(8,536)
Proceeds from redemption of marketable securities					327,779	18,711
Purchase of marketable securities and investments					(385,760)	(68,136)
Proceeds from Storage Transactions, net of cash contributed					3,239	61,593
Proceeds from Shredding Transactions					12,614	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					(24,207)	0
Other, net					(2,656)	(2,677)
Net cash provided by (used in) investing activities					(79,389)	955
Cash flows from financing activities:
Proceeds from issuance of debt					55	2,225
Repayment of debt					(36)	(2,405)
Exercise of stock-based compensation awards					0	0
Dividends paid					(41)	(60)
Repurchase of common stock					0	0
Other, net					(311)	1,675
Net cash used in financing activities					(333)	1,435
Effect of exchange rate changes on cash and cash equivalents					(6,574)	(7,588)
Net decrease in cash and cash equivalents					(61,130)	18,369
Cash and cash equivalents at beginning of period					93,725	40,223
Cash and cash equivalents at end of period		32,595		58,592	32,595	58,592
Eliminations
Cash flows from operating activities:
Net income		(119,062)		(94,156)	(566,739)	(327,215)
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
Loss on investment in Shred-it Partnership					0	0
(Gain) loss on sale of investment in Shred-it Partnership					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					4,690	2,198
Uniforms and other rental items in service					(572)	(394)
Prepaid expenses and other current assets					0	0
Accounts payable					(1)	6
Accrued compensation and related liabilities					0	0
Accrued liabilities and other					724	746
Income taxes, current					0	0
Net cash provided by operating activities					(561,898)	(324,659)
Cash flows from investing activities:
Capital expenditures					0	0
Proceeds from redemption of marketable securities					0	0
Purchase of marketable securities and investments					7,037	(56,544)
Proceeds from Storage Transactions, net of cash contributed					0	0
Proceeds from Shredding Transactions					0	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					555,585	381,949
Net cash provided by (used in) investing activities					562,622	325,405
Cash flows from financing activities:
Proceeds from issuance of debt					0	0
Repayment of debt					(724)	(746)
Exercise of stock-based compensation awards					0	0
Dividends paid					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 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