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Commitments and Contingencies (Details Textual) (USD $)
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3 Months Ended | |
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Aug. 31, 2013
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May 31, 2013
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| Commitments and Contingencies (Textual) | ||
| Commitments to purchase capital assets | $ 7,700,000 | $ 9,900,000 |
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Line of Credit [Member]
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| Line of Credit Facility [Line Items] | ||
| Amount outstanding | 0 | |
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Revolving Credit Facility [Member]
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| Line of Credit Facility [Line Items] | ||
| Maximum amount outstanding during period | 25,000,000 | |
| Interest rate on amount borrowed | 3.25% | |
| Maximum borrowing capacity | 500,000,000 | |
| Expiration date | Jun. 21, 2018 | |
| Amount outstanding | 0 | |
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Standby Letters of Credit [Member]
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| Line of Credit Facility [Line Items] | ||
| Amount available | 35,500,000 | 36,800,000 |
| Expiration date range of letters of credit | December 2013 and July 2014 | |
| Irrevocable stand by letters of credit amount outstanding | $ 0 |
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- Details
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- Definition
Expiry date range of letters of credit. No definition available.
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- Definition
Irrevocable standby letters of credit amount available. No definition available.
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- Definition
Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments. No definition available.
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- Definition
The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. No definition available.
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- Definition
Amount borrowed under the credit facility as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Date the credit facility terminates, in CCYY-MM-DD format. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The effective interest rate during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Maximum amount borrowed under the credit facility at any time during the period. No definition available.
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- Definition
Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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