Commitments and Contingencies - Additional Information (Detail) (USD $)	Apr. 30, 2014	Jul. 31, 2013
Commitments and Contingencies (Textual) [Abstract]
Purchase commitment of company	$ 1,000,000
Letters of credit outstanding	3,800,000
Letter of credit expires by April 30, 2015	1,000,000
Letter of credit expires in August 2015	2,800,000
Aggregate surety and performance bonds outstanding	9,900,000
Refundable customer deposits	48,487,000	28,663,000
IDT Payment Services and IDT Financial Services [Member]
Commitments and Contingencies (Textual) [Abstract]
Restricted Cash and Cash Equivalents	$ 9,600,000	$ 7,800,000