Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 904	$ (1,011)	$ (518)	$ (3,009)
Other comprehensive (loss) income:
Change in unrealized loss on available-for-sale securities		3		1
Foreign currency translation adjustments	(513)	(41)	(1,717)	483
Other comprehensive (loss) income	(513)	(38)	(1,717)	484
Comprehensive income (loss)	391	(1,049)	(2,235)	(2,525)
Comprehensive loss (income) attributable to noncontrolling interests	28	(300)	(63)	(601)
Comprehensive income (loss) attributable to IDT Corporation	$ 419	$ (1,349)	$ (2,298)	$ (3,126)