Acquisitions - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed - Oylo and Fiix Inc. (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2020	Sep. 30, 2020
Purchase Price Allocation
Goodwill	$ 1,902.2	$ 1,650.3
Oylo And Fiix Inc.
Purchase Price Allocation
Accounts receivable	6.2
All other assets	1.7
Goodwill	221.8
Intangible assets	72.1
Total assets acquired	301.8
Less: Liabilities assumed	(10.5)
Less: Deferred income taxes	(4.1)
Net assets acquired	287.2
Purchase Consideration
Total purchase consideration, net of cash acquired	$ 287.2

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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