Commitments and Contingencies (Details) $ in Millions	9 Months Ended
	May 31, 2020 USD ($) financial_institution	Aug. 31, 2019 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Purchase commitment, remaining minimum amount committed		$ 69.9
Letters of credit outstanding	$ 2.9
Number of financial institutions in which cash and cash equivalents are maintained | financial_institution	5
Concentration risk benchmark, percentage of total revenue	3.00%
Largest individual client percent of total subscriptions (as a percent)	2.50%
Percentage of subscription from ten largest clients (as a percent)	15.00%
Receivable reserve	$ 7.4	$ 10.5