Revenue Recognition (Details 1) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2018	Oct. 31, 2017
Revenue from External Customer [Line Items]
Revenues, Total	$ 362,316	$ 393,555
Outside the United States:
Total outside the United States	126,634	129,711
United States [Member]
Revenue from External Customer [Line Items]
Revenues, Total	235,682	263,844
United Kingdom [Member]
Outside the United States:
Total outside the United States	54,400	60,531
Netherlands [Member]
Outside the United States:
Total outside the United States	50,922	49,709
Other [Member]
Outside the United States:
Total outside the United States	21,312	19,471
Telecom & Payment Services [Member]
Revenue from External Customer [Line Items]
Revenues, Total	351,849	385,082
Outside the United States:
Total outside the United States	124,099	127,904
Telecom & Payment Services [Member] | United States [Member]
Revenue from External Customer [Line Items]
Revenues, Total	227,750	257,178
Telecom & Payment Services [Member] | United Kingdom [Member]
Outside the United States:
Total outside the United States	54,392	60,531
Telecom & Payment Services [Member] | Netherlands [Member]
Outside the United States:
Total outside the United States	50,922	49,709
Telecom & Payment Services [Member] | Other [Member]
Outside the United States:
Total outside the United States	18,785	17,664
Total net2phone [Member]
Revenue from External Customer [Line Items]
Revenues, Total	10,467	7,788
Outside the United States:
Total outside the United States	2,535	1,807
Total net2phone [Member] | United States [Member]
Revenue from External Customer [Line Items]
Revenues, Total	7,932	5,981
Total net2phone [Member] | United Kingdom [Member]
Outside the United States:
Total outside the United States	8
Total net2phone [Member] | Netherlands [Member]
Outside the United States:
Total outside the United States
Total net2phone [Member] | Other [Member]
Outside the United States:
Total outside the United States	2,527	1,807
All Other [Member]
Revenue from External Customer [Line Items]
Revenues, Total		685
Outside the United States:
Total outside the United States
All Other [Member] | United States [Member]
Revenue from External Customer [Line Items]
Revenues, Total		685
Outside the United States:
Total outside the United States
All Other [Member] | United Kingdom [Member]
Outside the United States:
Total outside the United States
All Other [Member] | Netherlands [Member]
Outside the United States:
Total outside the United States
All Other [Member] | Other [Member]
Outside the United States:
Total outside the United States