Schedule of Accumulated Balances for Each Classification of Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2022	Apr. 30, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance			$ (10,183)
Other comprehensive loss attributable to IDT Corporation	$ (253)	$ 567	(1,158)	$ (980)
Ending balance	(11,341)		(11,341)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance			(9)
Other comprehensive loss attributable to IDT Corporation			(547)
Ending balance	(556)		(556)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance			(10,174)
Other comprehensive loss attributable to IDT Corporation			(611)
Ending balance	$ (10,785)		$ (10,785)