Commitments and Contingencies (Details Textual) - USD ($) |
3 Months Ended | 12 Months Ended |
|---|---|---|
Aug. 31, 2015 |
May. 31, 2015 |
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| Commitments and Contingencies (Textual) | ||
| Commitments to purchase capital assets | $ 11,500,000 | $ 9,500,000 |
| Line of Credit [Member] | ||
| Line of Credit Facility [Line Items] | ||
| Amount outstanding | 0 | |
| Revolving Credit Facility [Member] | ||
| Line of Credit Facility [Line Items] | ||
| Amount outstanding | $ 0 | |
| Line of credit facility, initial term | 5 years | |
| Maximum amount outstanding during period | $ 200,000,000 | |
| Interest rate on amount borrowed | 3.25% | |
| Maximum borrowing capacity | $ 1,000,000,000 | $ 750,000,000 |
| Expiration date | Aug. 05, 2020 | Jun. 21, 2018 |
| Standby Letters of Credit [Member] | ||
| Line of Credit Facility [Line Items] | ||
| Amount available | $ 43,000,000 | $ 43,000,000 |
| Expiration date range of letters of credit | December 2015 and July 2016 | |
| Irrevocable stand by letters of credit amount outstanding | $ 0 |
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- Definition Commitments and contingencies. No definition available.
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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 Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. 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 The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. 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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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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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