Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2015	Oct. 31, 2014
Segment Reporting Information [Line Items]
Revenues	$ 390,578	$ 412,878
Income (loss) from operations	$ 7,925	79,607
Gain on sale of interest in Fabrix Systems Ltd.		75,145
Operating Segments [Member] \| Telecom Platform Services [Member]
Segment Reporting Information [Line Items]
Revenues	$ 385,688	403,787
Income (loss) from operations	9,726	$ 5,670
Gain on sale of interest in Fabrix Systems Ltd.
Operating Segments [Member] \| Consumer Phone Services [Member]
Segment Reporting Information [Line Items]
Revenues	1,828	$ 2,311
Income (loss) from operations	339	$ 355
Gain on sale of interest in Fabrix Systems Ltd.
Operating Segments [Member] \| All Other [Member]
Segment Reporting Information [Line Items]
Revenues	3,062	$ 6,780
Income (loss) from operations	$ 429	76,537
Gain on sale of interest in Fabrix Systems Ltd.		$ 75,145
Operating Segments [Member] \| Corporate [Member]
Segment Reporting Information [Line Items]
Revenues
Income (loss) from operations	$ (2,569)	$ (2,955)
Gain on sale of interest in Fabrix Systems Ltd.

Amount of gain (loss) on sale or disposal of equity in securities of subsidiaries.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (13)(g)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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