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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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- Definition

A description of the origin, nature, and characteristics of the tax credit carryforward.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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Income Tax and New Jersey Corporation Business Tax (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Sep. 30, 2017
Income Tax and New Jersey Corporation Business Tax (Textual)
Benefit from income taxes	$ 1,416	$ (14,415)
Tax credits to be received			$ 21,100
Tax credit, description	In September 2017, the Company, IDT Domestic Telecom, Inc. (a subsidiary of the Company) and certain other affiliates, were certified by the New Jersey Economic Development Authority as having met all of the requirements of the Grow New Jersey Assistance Act Tax Credit Program. The corporation business tax credits to be received are a maximum of $21.1 million. The Company may claim a tax credit each tax year for ten years beginning in 2017. The tax credit can be applied to 100% of the Company's New Jersey tax liability each year, and the unused amount of the annual credit can be carried forward. In addition, the Company may apply for a tax credit transfer certificate to sell unused tax credits to another business. The tax credits must be sold for no less than 75% of the value of the tax credits. The tax credits are subject to reduction, forfeiture and recapture if, among other things, the number of full-time employees declines below the program or statewide minimum.
Elmion Netherlands B.V. [Member]
Income Tax and New Jersey Corporation Business Tax (Textual)
Benefit from income taxes		$ 16,600