Revenue (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Feb. 29, 2020	Feb. 29, 2020	Aug. 31, 2019
Deferred revenue	$ 56.9	$ 56.9	$ 65.8
Other long-term liabilities	2.6	2.6	3.6
Remaining performance obligations	$ 82.7	$ 82.7
Percentage of remaining performance obligations will be recognized over the next 12 months	75.00%	75.00%
Subscription [Member]
Deferred revenue	$ 48.0	$ 48.0	$ 58.2
Deferred revenue recognized	$ 21.4	$ 42.5

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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