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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
	Mar. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Purchase Price Allocation
Goodwill		$ 3,625.9	$ 1,650.3	$ 1,071.1
Oylo And Fiix Inc.
Purchase Price Allocation
Accounts receivable	$ 6.0
Other assets	15.9
Goodwill	224.8
Intangible assets	69.6
Total assets acquired	316.3
Less: Liabilities assumed	(25.5)
Less: Deferred income taxes	(3.7)
Net assets acquired	287.1
Purchase Consideration
Total purchase consideration, net of cash acquired	$ 287.1