Fair Value of Financial Assets and Liabilities - Contractual Maturities of Available-for-Sale Debt Securities (Details) $ in Thousands	Jul. 31, 2015 USD ($)
Fair Value Disclosures [Abstract]
Due in one year or less	$ 44,695
Due in 1-2 years	5,001
Total Investments in debt securities	$ 49,696

Amount of debt securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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