Supplemental Guarantor Information (Details 2) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2012	May 31, 2012	Aug. 31, 2011	May 31, 2011
Current assets:
Cash and cash equivalents	$ 319,217	$ 339,825	$ 150,312	$ 438,106
Marketable securities	10,948	0
Accounts receivable, net	459,302	450,861
Inventories, net	241,699	251,205
Uniforms and other rental items in service	462,541	452,785
Income taxes, current	0	22,188
Prepaid expenses and other	30,170	24,704
Total current assets	1,523,877	1,541,568
Property and equipment, at cost, net	953,761	944,305
Goodwill	1,489,104	1,485,375
Service contracts, net	72,297	76,822
Other assets, net	113,196	112,836
Total assets	4,152,235	4,160,906	4,127,892
Current liabilities:
Accounts payable	110,906	94,840
Accrued compensation and related liabilities	40,531	91,214
Accrued liabilities	213,440	256,642
Income taxes, current	7,930	0
Deferred tax (asset) liability	10,668	2,559
Long-term debt due within one year	636	225,636
Total current liabilities	384,111	670,891
Long-term liabilities:
Long-term debt due after one year	1,309,012	1,059,166
Deferred income taxes	206,856	204,581
Accrued liabilities	97,841	87,133
Total long-term liabilities	1,613,709	1,350,880
Total shareholders' equity	2,154,415	2,139,135
Total liabilities and shareholders' equity	4,152,235	4,160,906
Cintas Corporation [Member]
Current assets:
Cash and cash equivalents	0	0	0	0
Marketable securities	0
Accounts receivable, net	0	0
Inventories, net	0	0
Uniforms and other rental items in service	0	0
Income taxes, current		0
Prepaid expenses and other	0	0
Total current assets	0	0
Property and equipment, at cost, net	0	0
Goodwill	0	0
Service contracts, net	0	0
Other assets, net	1,645,153	1,637,225
Total assets	1,645,153	1,637,225
Current liabilities:
Accounts payable	(465,247)	(465,247)
Accrued compensation and related liabilities	0	0
Accrued liabilities	0	0
Income taxes, current	0
Deferred tax (asset) liability	0	0
Long-term debt due within one year	0	0
Total current liabilities	(465,247)	(465,247)
Long-term liabilities:
Long-term debt due after one year	0	0
Deferred income taxes	0	0
Accrued liabilities	0	0
Total long-term liabilities	0	0
Total shareholders' equity	2,110,400	2,102,472
Total liabilities and shareholders' equity	1,645,153	1,637,225
Corp. 2 [Member]
Current assets:
Cash and cash equivalents	69,882	58,737	53,466	54,957
Marketable securities	0
Accounts receivable, net	336,900	327,442
Inventories, net	202,689	210,283
Uniforms and other rental items in service	341,438	337,298
Income taxes, current		5,296
Prepaid expenses and other	7,704	7,905
Total current assets	958,613	946,961
Property and equipment, at cost, net	603,680	600,565
Goodwill	0	0
Service contracts, net	67,134	71,337
Other assets, net	1,627,262	1,628,516
Total assets	3,256,689	3,247,379
Current liabilities:
Accounts payable	(510,373)	(475,624)
Accrued compensation and related liabilities	28,271	63,797
Accrued liabilities	41,394	67,651
Income taxes, current	540
Deferred tax (asset) liability	(558)	(538)
Long-term debt due within one year	885	225,866
Total current liabilities	(439,841)	(118,848)
Long-term liabilities:
Long-term debt due after one year	1,318,417	1,068,820
Deferred income taxes	(6)	(6)
Accrued liabilities	0	0
Total long-term liabilities	1,318,411	1,068,814
Total shareholders' equity	2,378,119	2,297,413
Total liabilities and shareholders' equity	3,256,689	3,247,379
Subsidiary Guarantors [Member]
Current assets:
Cash and cash equivalents	211,194	229,287	60,008	313,283
Marketable securities	0
Accounts receivable, net	82,233	81,243
Inventories, net	19,997	20,258
Uniforms and other rental items in service	105,298	101,435
Income taxes, current		3,642
Prepaid expenses and other	18,248	12,770
Total current assets	436,970	448,635
Property and equipment, at cost, net	261,647	259,744
Goodwill	1,420,051	1,419,535
Service contracts, net	261	326
Other assets, net	2,547,273	2,467,198
Total assets	4,666,202	4,595,438
Current liabilities:
Accounts payable	1,032,986	978,932
Accrued compensation and related liabilities	8,884	21,619
Accrued liabilities	160,562	176,220
Income taxes, current	20,991
Deferred tax (asset) liability	7,957	(87)
Long-term debt due within one year	(249)	(230)
Total current liabilities	1,231,131	1,176,454
Long-term liabilities:
Long-term debt due after one year	(10,253)	(11,288)
Deferred income taxes	201,124	199,404
Accrued liabilities	97,088	86,406
Total long-term liabilities	287,959	274,522
Total shareholders' equity	3,147,112	3,144,462
Total liabilities and shareholders' equity	4,666,202	4,595,438
Non-Guarantors [Member]
Current assets:
Cash and cash equivalents	38,141	51,801	36,838	69,866
Marketable securities	10,948
Accounts receivable, net	40,169	42,176
Inventories, net	10,893	10,781
Uniforms and other rental items in service	35,591	35,051
Income taxes, current		13,250
Prepaid expenses and other	4,218	4,029
Total current assets	139,960	157,088
Property and equipment, at cost, net	88,434	83,996
Goodwill	69,053	65,840
Service contracts, net	4,902	5,159
Other assets, net	758,233	759,439
Total assets	1,060,582	1,071,522
Current liabilities:
Accounts payable	15,521	18,760
Accrued compensation and related liabilities	3,376	5,798
Accrued liabilities	11,484	13,557
Income taxes, current	(13,601)
Deferred tax (asset) liability	3,269	3,184
Long-term debt due within one year	0	0
Total current liabilities	20,049	41,299
Long-term liabilities:
Long-term debt due after one year	848	848
Deferred income taxes	5,738	5,183
Accrued liabilities	753	727
Total long-term liabilities	7,339	6,758
Total shareholders' equity	1,033,194	1,023,465
Total liabilities and shareholders' equity	1,060,582	1,071,522
Eliminations [Member]
Current assets:
Cash and cash equivalents	0	0	0	0
Marketable securities	0
Accounts receivable, net	0	0
Inventories, net	8,120	9,883
Uniforms and other rental items in service	(19,786)	(20,999)
Income taxes, current		0
Prepaid expenses and other	0	0
Total current assets	(11,666)	(11,116)
Property and equipment, at cost, net	0	0
Goodwill	0	0
Service contracts, net	0	0
Other assets, net	(6,464,725)	(6,379,542)
Total assets	(6,476,391)	(6,390,658)
Current liabilities:
Accounts payable	38,019	38,019
Accrued compensation and related liabilities	0	0
Accrued liabilities	0	(786)
Income taxes, current	0
Deferred tax (asset) liability	0	0
Long-term debt due within one year	0	0
Total current liabilities	38,019	37,233
Long-term liabilities:
Long-term debt due after one year	0	786
Deferred income taxes	0	0
Accrued liabilities	0	0
Total long-term liabilities	0	786
Total shareholders' equity	(6,514,410)	(6,428,677)
Total liabilities and shareholders' equity	$ (6,476,391)	$ (6,390,658)