Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Noncontrolling Interests	IDT Corp Class A common stock	IDT Corp Class B common stock	IDT Corp Additional Paid-In Capital	IDT Corp Treasury Stock	IDT Corp Accumulated Other Comprehensive Income	IDT Corp Accumulated Deficit
Balance at Jul. 31, 2013	$ 89,136	$ 533	$ 33	$ 243	$ 388,533	$ (98,836)	$ 2,341	$ (203,711)
Balance, Shares at Jul. 31, 2013			3,272	24,275
Dividends declared	(11,798)							(11,798)
Restricted Class B common stock purchased from employees	(1,005)					(1,005)
Exercise of stock options	609	3			606
Exercise of stock options, Shares				46
Stock-based compensation	5,362	30			5,332
Restricted stock issued to employees and directors				$ 2	(2)
Restricted stock issued to employees and directors, Shares				194
Stock issued for matching contributions to the 401(k) Plan	1,168			$ 1	1,167
Stock issued for matching contributions to the 401(k) Plan, Shares				72
Purchases of stock of subsidiary	(1,133)	21			(1,154)
Distributions to noncontrolling interests	(1,888)	(1,888)
Zedge Spin-Off	(1,624)				(1,624)
Other comprehensive income (loss)	1,327						1,327
Net income for the year ended July	21,010	2,226						18,784
Balance at Jul. 31, 2014	101,164	925	$ 33	$ 246	392,858	(99,841)	3,668	(196,725)
Balance, Shares at Jul. 31, 2014			3,272	24,587
Dividends declared	(47,594)							(47,594)
Restricted Class B common stock purchased from employees	(2,777)					(2,777)
Repurchases of Class B common stock through repurchase program	(425)					(425)
Exercise of stock options	3,424			$ 2	3,422
Exercise of stock options, Shares				245
Stock-based compensation	5,666	62			5,604
Restricted stock issued to employees and directors				$ 4	(4)
Restricted stock issued to employees and directors, Shares				373
Stock issued for matching contributions to the 401(k) Plan	1,267			$ 1	1,266
Stock issued for matching contributions to the 401(k) Plan, Shares				71
Purchase of Class B common stock from Howard S. Jonas	(7,500)					(7,500)
Other	9	9
Distributions to noncontrolling interests	(2,050)	(2,050)
Sale of interest in Fabrix Systems Ltd.	640	538					102
Other comprehensive income (loss)	(2,999)						(2,999)
Net income for the year ended July	86,115	1,625						84,490
Balance at Jul. 31, 2015	134,940	1,109	$ 33	$ 253	403,146	(110,543)	771	(159,829)
Balance, Shares at Jul. 31, 2015			3,272	25,276
Dividends declared	(17,358)							(17,358)
Restricted Class B common stock purchased from employees	(134)					(134)
Repurchases of Class B common stock through repurchase program	(4,639)					(4,639)
Exercise of subsidiary stock options	9	9
Stock-based compensation	2,680				2,680
Restricted stock issued to employees and directors
Restricted stock issued to employees and directors, Shares				12
Stock issued for matching contributions to the 401(k) Plan	1,411			$ 1	1,410
Stock issued for matching contributions to the 401(k) Plan, Shares				95
Other	2				2
Sale of Zedge equity prior to the spin-off	374				374
Distributions to noncontrolling interests	(1,834)	(1,834)
Zedge Spin-Off	(11,062)	(722)			(11,369)		1,029
Other comprehensive income (loss)	(5,544)						(5,544)
Net income for the year ended July	25,358	1,844						23,514
Balance at Jul. 31, 2016	$ 124,203	$ 406	$ 33	$ 254	$ 396,243	$ (115,316)	$ (3,744)	$ (153,673)
Balance, Shares at Jul. 31, 2016			3,272	25,383