Description of Business, Basis of Presentation, and Significant Accounting Policies (Narrative) (Details) $ in Millions |
3 Months Ended | 12 Months Ended | |
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Aug. 31, 2017
USD ($)
segment
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Aug. 31, 2016
USD ($)
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May 31, 2017
USD ($)
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| Accounting Policies [Line Items] | |||
| Number of reportable segments | segment | 1 | ||
| Maximum individual workers' compensation claims liability | $ 1.3 | $ 1.3 | |
| Maximum individual health insurance claims liability | 0.3 | $ 0.3 | |
| Stock-based compensation costs recognized | $ 8.7 | $ 9.1 | |
| Germany [Member] | Total Revenue [Member] | Geographic Concentration Risk [Member] | |||
| Accounting Policies [Line Items] | |||
| Percentage of total revenue less than one percent | 1.00% | 1.00% | |
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- Definition Accounting Policies [Line Items] No definition available.
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- Definition Maximum Individual Claims Liability Health Insurance No definition available.
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- Definition Maximum individual claims liability workers compensation insurance. No definition available.
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. No definition available.
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