Schedule of Accumulated Balances for Each Classification of Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (10,183)	$ (7,410)	$ (4,858)
Other comprehensive loss attributable to IDT Corporation	(1,122)	(2,773)	(2,552)
Ending balance	(11,305)	(10,183)	(7,410)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(9)	42
Other comprehensive loss attributable to IDT Corporation	(537)	(51)	42
Ending balance	(546)	(9)	42
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(10,174)	(7,452)	(4,858)
Other comprehensive loss attributable to IDT Corporation	(585)	(2,722)	(2,594)
Ending balance	$ (10,759)	$ (10,174)	$ (7,452)