Income Taxes (Details Textual) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Dec. 22, 2017	Oct. 31, 2018	Jan. 31, 2018	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017	Sep. 30, 2017
Income Taxes (Textual)
Federal net operating loss carryforwards				$ 155,000
Net operating loss carryforwards expiration date				2018
Foreign net operating losses				$ 143,000
Foreign net operating loss, no expiration				120,000
Foreign net operating loss, expiration in two to ten years				22,000
Foreign net operating loss, expiration in twenty years				1,000
Cumulative undistributed foreign earnings				$ 337,000
Tax credits to be received							$ 21,100
Tax credit, description				The Company may claim a tax credit each tax year for ten years beginning in 2018. The tax credit can be applied to 100% of the Company's New Jersey tax liability each year, and the unused amount of the annual credit can be carried forward. In addition, the Company may apply for a tax credit transfer certificate to sell unused tax credits to another business. The tax credits must be sold for no less than 75% of the value of the tax credits.
(Provision for) benefit from income taxes		$ 1,200	$ (3,300)	$ (123)	$ (2,902)	$ 2,021
Income tax expense on deferred tax assets
U.S. federal statutory corporate tax rate					26.90%
U.S. federal statutory tax rate, thereafter					21.00%
Federal net operating loss carryforwards used to offset transition tax				11,000	$ 12,000
Decrease in deferred tax assets				4,589	5,668
U.S. income				$ 600
Dividends received deduction for foreign source				100.00%
Net2phone [Member]
Income Taxes (Textual)
Net operating losses, federal				$ 70,000
Net operating losses expiration, description				Expire through fiscal 2027.
Losses limited under internal revenue code				$ 7,000
Rafael Spin-Off [Member]
Income Taxes (Textual)
Decrease to deferred tax assets and valuation allowance					6,000
US Deferred Tax Assets [Member]
Income Taxes (Textual)
Income tax expense on deferred tax assets						11,100
Valuation Allowance of Deferred Tax Assets [Member]
Income Taxes (Textual)
(Provision for) benefit from income taxes					$ 3,300
Elmion Netherlands B V [Member]
Income Taxes (Textual)
(Provision for) benefit from income taxes						$ 16,600
Minimum [Member]
Income Taxes (Textual)
U.S. federal statutory corporate tax rate	21.00%
Maximum [Member]
Income Taxes (Textual)
U.S. federal statutory corporate tax rate	35.00%