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Acquisitions Business Combinations Additional Information (Details) - USD ($) $ in Millions	9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Acquired Indefinite-lived Intangible Assets [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired	$ 224.4	$ 151.5
Asset Acquisition, Consideration Transferred, Contingent Consideration	34.0
Asset Acquisition, Contingent Consideration, Liability	$ 15.3
2020 Acquisitions
Acquired Indefinite-lived Intangible Assets [Line Items]
Goodwill, Acquired During Period			$ 129.5
Business Acquisition, Goodwill, Expected Tax Deductible Amount			$ 77.1

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Amount of contingent consideration recognized as part of consideration transferred in asset acquisition.

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Amount of liability recognized from contingent consideration in asset acquisition.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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