Earnings Per Common Share (Detail) - shares	3 Months Ended	6 Months Ended
Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Earnings Per Share [Abstract]
Weighted-average shares outstanding for basic earnings per share (in shares)	55,198,756	52,806,981	55,146,915	52,766,739
Unvested restricted stock units (in shares)	197,360	60,706	163,470	116,906
Weighted-average shares outstanding assuming dilution (in shares)	55,396,116	52,867,687	55,310,385	52,883,645
Antidilutive stock options, unvested restricted stock units outstanding (in shares)	160,091	317,234	213,395	234,756

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- References

No definition available.

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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
-Topic 260
-SubTopic 10
-Section 45
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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.

+ References

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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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