Schedule of Weighted-average Number of Shares Used in the Calculation of Basic and Diluted Earnings Per Share (Details) - shares shares in Thousands	3 Months Ended	9 Months Ended
Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2022	Apr. 30, 2021
Earnings per share attributable to IDT Corporation common stockholders:
Basic weighted-average number of shares	25,901	25,530	25,706	25,475
Stock options	301	295	575	101
Non-vested restricted Class B common stock	3	311	174	327
Diluted weighted-average number of shares	26,205	26,136	26,455	25,903

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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.

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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.

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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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