Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Segment Reporting Information [Line Items]
Revenues	$ 341,255	$ 365,410	$ 1,053,044	$ 1,154,848
Income (loss) from operations	2,749	(1,693)	5,574	(2,090)
Severance	553	3,658	553	4,293
Other operating expense	(120)	(345)	(405)	(1,970)
Operating Segments [Member] \| Telecom & Payment Services [Member]
Segment Reporting Information [Line Items]
Revenues	328,838	356,362	1,018,637	1,128,510
Income (loss) from operations	6,577	3,143	18,121	12,105
Severance	553	3,592	553	4,197
Other operating expense			215
Operating Segments [Member] \| net2phone [Member]
Segment Reporting Information [Line Items]
Revenues	12,417	9,086	34,407	25,172
Income (loss) from operations	(1,267)	(769)	(4,663)	(2,233)
Severance
Other operating expense			25
Operating Segments [Member] \| All Other [Member]
Segment Reporting Information [Line Items]
Revenues		(38)		1,166
Income (loss) from operations		(1,138)		(2,600)
Severance
Other operating expense
Operating Segments [Member] \| Corporate [Member]
Segment Reporting Information [Line Items]
Revenues
Income (loss) from operations	(2,561)	(2,929)	(7,884)	(9,362)
Severance		66		96
Other operating expense	$ (120)	$ (345)	$ (645)	$ (1,970)

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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).

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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