Earnings (Loss) Per Share (Details) - shares shares in Thousands	3 Months Ended	6 Months Ended
Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2019	Jan. 31, 2018
Weighted-average number of shares used in the calculation of basic and diluted earnings (loss) per share [Abstract]
Basic weighted-average number of shares	24,816	24,643	24,323	24,635
Effect of dilutive securities:
Stock options		10
Non-vested restricted Class B common stock	5	71
Diluted weighted-average number of shares	24,821	24,724	24,323	24,635

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options and warrants using the treasury stock method.

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Number of additional shares included in diluted EPS for potentially dilutive effect of nonvested equity-based payment award containing forfeitable rights to dividends or dividend equivalents, whether paid or unpaid.

+ References

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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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