Document and Entity Information	9 Months Ended
	Apr. 30, 2012	Jun. 06, 2012 Class Common Stock	Jun. 06, 2012 Class B Common Stock
Entity Registrant Name	IDT CORP
Entity Central Index Key	0001005731
Amendment Flag	false
Current Fiscal Year End Date	--07-31
Document Type	10-Q
Document Period End Date	Apr. 30, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q3
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		1,574,326	21,189,279