Commitments and Contingencies (Details 1) - USD ($) $ in Thousands	Jul. 31, 2015	Jul. 31, 2014
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash and cash equivalents-short-term	$ 91,035	$ 65,706
Restricted cash and cash equivalents-long-term		2,763
Total restricted cash and cash equivalents	$ 91,035	68,469
Restricted Cash And Cash Equivalents-Short-Term [Member] \| Letters of credit related [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash and cash equivalents-short-term	3,163	665
Restricted Cash And Cash Equivalents-Short-Term [Member] \| IDT Financial Services customer deposits [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash and cash equivalents-short-term	87,613	64,415
Restricted Cash And Cash Equivalents-Short-Term [Member] \| Other [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash and cash equivalents-short-term	$ 259	626
Restricted Cash And Cash Equivalents-Long-Term [Member] \| Letters of credit related [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash and cash equivalents-long-term		$ 2,763

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

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- Definition

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