Schedule of Difference Between Basic and Diluted EPS as Result of Restricted Stock Units and Unvested Restricted Stock (Detail) - shares	3 Months Ended	9 Months Ended
Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Earnings Per Share [Abstract]
Weighted-average shares outstanding for basic earnings per share	55,063,473	52,695,365	53,515,491	52,667,016
Unvested restricted stock units	102,594	158,176	112,136	177,024
Weighted-average shares outstanding assuming dilution	55,166,067	52,853,541	53,627,627	52,844,040

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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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