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Acquisitions - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed - Oylo and Fiix Inc. (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Mar. 31, 2021	Sep. 30, 2020
Purchase Price Allocation
Goodwill		$ 1,895.0	$ 1,650.3
Oylo And Fiix Inc.
Purchase Price Allocation
Accounts receivable	$ 6.0
All other assets	17.8
Goodwill	219.8
Intangible assets	73.4
Total assets acquired	317.0
Less: Liabilities assumed	(25.5)
Less: Deferred income taxes	(4.4)
Net assets acquired	287.1
Purchase Consideration
Total purchase consideration, net of cash acquired	$ 287.1