XML 52 R41.htm IDEA: XBRL DOCUMENT v3.19.1

Revenue Recognition (Details 2) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jan. 31, 2019	Jan. 31, 2019
Contract Liability [Member]
Offsetting Liabilities [Line Items]
Revenue recognized in the period from amounts included in the contract liability balance at the beginning of the period	$ 16,488	$ 18,624

X

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_OffsettingLiabilitiesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=idt_ContractLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: