Defined Contribution Plans - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Jul. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Participants to contribute	20.00%
Discretionary matching contributions	50.00%
Defined benefit plan compensation	6.00%
Company's cost for contributions to the Plan	$ 911
Plan for matching contributions	92,843

Defined Contribution Plan Employer Matching Contribution In Employer Shares

No definition available.

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- Definition

Defined Contribution Plan Employer Matching Contribution Limit Percent

+ References

No definition available.

+ Details

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- Details

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 11

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

+ Details

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay, by the terms of the plan, that the employer may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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