Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2019	Jan. 31, 2018
Accounting Policies [Abstract]
Service revenue	$ 1,449	$ 151	$ 2,885	$ 207
Product revenue	37		123
Total operating revenues	$ 1,486	$ 151	$ 3,008	$ 207