Carrying value as of the balance sheet date of obligations incurred through that date and payable for sales commissions.

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Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019	Jul. 31, 2019
Concentration Risk [Line Items]
Contract with customer, liability, revenue recognized			$ 148.4	$ 68.2
Revenue, remaining performance obligation	$ 608.5		608.5
Accrued sales commissions	$ 5.7		$ 5.7		$ 9.0
Minimum
Concentration Risk [Line Items]
Contract with customer, term of contract			1 year
Maximum
Concentration Risk [Line Items]
Contract with customer, term of contract			3 years
Subscription and Support \| Sales Revenue, Net \| Product Concentration Risk \| Transferred over Time
Concentration Risk [Line Items]
Revenue, percentage	98.00%	97.00%	98.00%	98.00%