Defined Contribution Plans - Additional Information (Detail) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Defined Contribution Plans [Abstract]
Maximum percentage of participants contribution	20.00%
Percentage of discretionary matching contributions	50.00%
Defined benefit plan compensation	6.00%
Company's cost for contributions to the Plan	$ 1.1	$ 1.1	$ 0.9
Number of shares issed for contribution plan	72,281	51,861	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

+ 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 the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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