Schedule of Difference Between Basic and Diluted EPS as Result of Restricted Stock Units and Unvested Restricted Stock (Detail) - shares	12 Months Ended
Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Earnings Per Share [Abstract]
Weighted-average shares outstanding for basic earnings per share	52,674,161	52,562,723	52,458,789
Unvested restricted stock and restricted stock units	179,199	195,719	131,727
Weighted-average shares outstanding assuming dilution	52,853,360	52,758,442	52,590,516

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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