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           Related Parties 
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        12 Months Ended | 
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           May 31, 2013 
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| Related Party Transactions [Abstract] | |
| Related Parties | 
 Related Parties 
During fiscal years 2013, 2012, and 2011, the Company purchased approximately $6.5 million, $2.6 million, and $5.7 million, respectively, of data processing equipment and software from EMC Corporation. The Chairman, President, and Chief Executive Officer of EMC Corporation is a member of the Company’s Board.
 
During fiscal years 2013, 2012, and 2011, the Company purchased approximately $1.6 million, $1.8 million, and $1.8 million, respectively, of office supplies from Staples, Inc. The President of Staples North American Commercial is a member of the Company’s Board.
 
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- Definition 
          The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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