Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Oct. 31, 2015	Oct. 31, 2014
Consolidated Statements of Income [Abstract]
Revenues	$ 390,578	$ 412,878
Costs and expenses:
Direct cost of revenues (exclusive of depreciation and amortization)	324,511	343,807
Selling, general and administrative (i)	53,090	56,999
Depreciation and amortization	$ 5,052	4,405
Research and development		1,656
Severance		1,549
Total costs and expenses	$ 382,653	408,416
Gain on sale of interest in Fabrix Systems Ltd.		75,145
Income from operations	$ 7,925	79,607
Interest income (expense), net	158	(90)
Other (expense) income, net	(610)	1,323
Income before income taxes	7,473	80,840
Provision for income taxes	(2,898)	(486)
Net income	4,575	80,354
Net income attributable to noncontrolling interests	(382)	(199)
Net income attributable to IDT Corporation	$ 4,193	$ 80,155
Earnings per share attributable to IDT Corporation common stockholders:
Basic	$ 0.18	$ 3.52
Diluted	$ 0.18	$ 3.47
Weighted-average number of shares used in calculation of earnings per share:
Basic	22,935	22,755
Diluted	22,969	23,091
Dividends declared per common share	$ 0.18	$ 0.85
(i) Stock-based compensation included in selling, general and administrative expenses	$ 771	$ 848