Other Noncontrolling Interest.

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Defined contribution plan employer matching contribution in employer shares value of shares.

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Repurchase of common stock under stock repurchase program.

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Repurchase Of Restricted Stock

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Stock based compensation.

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Stockholders equity decrease from deconsolidation due to subsidiary sale.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Value of stock issued as a result of the exercise of stock options.

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Equity (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014
Changes in the components of equity
Beginning Balance			$ 101,164
Dividends declared ($1.85 per share)			(43,171)us-gaap_DividendsCash
Restricted Class B common stock purchased from employees			(279)idt_RepurchaseOfRestrictedStock
Repurchases of Class B common stock through repurchase program			(424)
Exercise of stock options			3,317
Stock issued for matching contributions to the 401(k) Plan			1,266
Other			9
Sale of interest in Fabrix Systems Ltd.			640
Distributions to noncontrolling interests			(1,450)
Stock-based compensation			4,492idt_StockBasedCompensation
Comprehensive income:
Net income	1,123us-gaap_ProfitLoss	5,599us-gaap_ProfitLoss	84,234us-gaap_ProfitLoss	12,622us-gaap_ProfitLoss
Other comprehensive loss	1,062	531	(2,900)	1,713
Comprehensive income	2,185	6,130	81,334	14,335
Ending Balance	146,898		146,898
Attributable to IDT Corporation [Member]
Changes in the components of equity
Beginning Balance			100,239
Dividends declared ($1.85 per share)			(43,171)
Restricted Class B common stock purchased from employees			(279)
Repurchases of Class B common stock through repurchase program			(424)
Exercise of stock options			3,317
Stock issued for matching contributions to the 401(k) Plan			1,266
Other
Sale of interest in Fabrix Systems Ltd.			102
Distributions to noncontrolling interests
Stock-based compensation			4,430
Comprehensive income:
Net income			83,231
Other comprehensive loss			(2,900)
Comprehensive income			80,331
Ending Balance	145,811		145,811
Noncontrolling Interests [Member]
Changes in the components of equity
Beginning Balance			925
Dividends declared ($1.85 per share)
Restricted Class B common stock purchased from employees
Repurchases of Class B common stock through repurchase program
Exercise of stock options
Stock issued for matching contributions to the 401(k) Plan
Other			9
Sale of interest in Fabrix Systems Ltd.			538
Distributions to noncontrolling interests			(1,450)
Stock-based compensation			62
Comprehensive income:
Net income			1,003
Other comprehensive loss
Comprehensive income			1,003
Ending Balance	$ 1,087		$ 1,087