Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 21,010	$ 13,444	$ 38,785
Other comprehensive income (loss):
Change in unrealized (loss) gain on available-for-sale securities	(8)	(1)	4
Foreign currency translation adjustments	1,335	2,092	(2,272)
Other comprehensive income (loss)	1,327	2,091	(2,268)
COMPREHENSIVE INCOME	22,337	15,535	36,517
Comprehensive income attributable to noncontrolling interests	(2,226)	(1,789)	(256)
COMPREHENSIVE INCOME ATTRIBUTABLE TO IDT CORPORATION	$ 20,111	$ 13,746	$ 36,261