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Accumulated Other Comprehensive Loss (Details Textual) - Unrealized (loss) gain on available-for-sale securities [Member] $ in Thousands | 12 Months Ended
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Jul. 31, 2017 USD ($)
Rafael Pharmaceuticals Inc [Member] |
Schedule of accumulated balances for each classification of other comprehensive income (loss) |
Net other comprehensive income (loss) attributable to IDT Corporation | $ 2,100
Marketable Securities [Member] |
Schedule of accumulated balances for each classification of other comprehensive income (loss) |
Net other comprehensive income (loss) attributable to IDT Corporation | $ 26

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- Definition Amount of increase (decrease) in other comprehensive income, after tax, from changes classified as other. + References No definition available. + Details
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