Balance Sheet Components (Details) - USD ($)	3 Months Ended	12 Months Ended
	Apr. 30, 2020	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018	May 31, 2020
Deferred Revenue Arrangement [Line Items]
Property and equipment pledged as collateral		$ 0	$ 0
Depreciation expense		$ 14,500,000	9,700,000	$ 7,700,000
Remaining Weighted-Average Useful Life (in years)		2 years 8 months 12 days
Amortization		$ 1,400,000	1,000,000.0	400,000
Goodwill		340,877,000	340,877,000	340,900,000
Amortization of intangible assets		26,800,000	$ 29,100,000	$ 27,500,000
Cost of investment		$ 1,200,000			$ 1,000,000.0
Impairment loss	$ 10,700,000
Software Development | Minimum
Deferred Revenue Arrangement [Line Items]
Remaining Weighted-Average Useful Life (in years)		3 years
Software Development | Maximum
Deferred Revenue Arrangement [Line Items]
Remaining Weighted-Average Useful Life (in years)		5 years