Goodwill, Service Contracts and Other Assets (Information Regarding Service Contracts and Other Assets) (Details) (USD $)	Feb. 28, 2014		May 31, 2013
Information regarding service contracts and other assets
Service contracts, Net	$ 83,972,000		$ 92,153,000
Other Assets, Carrying Amount	218,523,000		202,099,000
Other Assets, Accumulated Amortization	80,728,000		77,709,000
Other Assets, Net	137,795,000		124,390,000
Cash surrender value of insurance policies	85,900,000		73,000,000
Equity method investments	29,100,000		27,600,000
Cost method investments	800,000		900,000
Noncompete and consulting agreements
Information regarding service contracts and other assets
Other Assets, Carrying Amount	79,009,000		77,863,000
Other Assets, Accumulated Amortization	74,856,000		72,970,000
Other Assets, Net	4,153,000		4,893,000
Investments
Information regarding service contracts and other assets
Other Assets, Carrying Amount	115,809,000	[1]	101,525,000	[1]
Other Assets, Accumulated Amortization	0	[1]	0	[1]
Other Assets, Net	115,809,000	[1]	101,525,000	[1]
Other
Information regarding service contracts and other assets
Other Assets, Carrying Amount	23,705,000		22,711,000
Other Assets, Accumulated Amortization	5,872,000		4,739,000
Other Assets, Net	17,833,000		17,972,000
Service Contracts
Information regarding service contracts and other assets
Service contracts, Carrying Amount	426,788,000		420,499,000
Service contracts, Accumulated Amortization	342,816,000		328,346,000
Service contracts, Net	$ 83,972,000		$ 92,153,000

[1] Investments at February 28, 2014, include the cash surrender value of insurance policies of $85.9 million, equity method investments of $29.1 million and cost method investments of $0.8 million. Investments at May 31, 2013, include the cash surrender value of insurance policies of $73.0 million, equity method investments of $27.6 million and cost method investments of $0.9 million. During the second quarter of fiscal 2013, Cintas sold stock of an equity method investment for a gain of $8.5 million.