Goodwill and intangible assets (Details) - Schedule of change in the carrying amount of intangible assets - USD ($) $ in Thousands	9 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Schedule of change in the carrying amount of intangible assets [Abstract]
Gross, Beginning Balance	$ 27,238
Accumulated Amortization, Beginning Balance	(26,206)
Net, Beginning Balance	1,032
Amortization expense, Accumulated Amortization	(451)	$ (741)
Amortization expense, Net	(451)	$ (741)
Foreign currency translation, Gross	47
Foreign currency translation, Accumulated Amortization	(40)
Foreign currency translation, Net	7
Gross, Ending Balance	27,285
Accumulated Amortization, Ending Balance	(26,697)
Net, Ending Balance	$ 588