Additional Information for Certain Balance Sheet Accounts (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2013	Jul. 31, 2012
Supplemental Balance Sheet Information [Line Items]
Total unbilled receivables	$ 6,331	$ 7,652
Long-term portion of unbilled receivables	2,443	2,678
Total deferred revenue	11,636	12,267
Long-term portion of deferred revenue	$ 1,366	$ 716

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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-Publisher FASB

-Name Accounting Standards Codification

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The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of unbilled receivables under long-term contracts that have not been billed and were not billable.

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Amount of unbilled receivables under long-term contracts that have not been billed and were not billable that are expected to be collected after the next fiscal year.

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