Schedule of Difference Between Basic and Diluted EPS as Result of Restricted Stock Units and Unvested Restricted Stock (Detail) - shares	3 Months Ended
Oct. 31, 2018	Oct. 31, 2017
Earnings Per Share [Abstract]
Weighted-average shares outstanding for basic earnings per share	52,726,496	52,611,926
Unvested restricted stock units	173,107	206,437
Weighted-average shares outstanding assuming dilution	52,899,603	52,818,363

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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
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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