Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Consolidated Balance Sheets (Parenthetical) [Abstract]
Allowance for doubtful accounts	$ 20.8	$ 30.4
Accumulated depreciation	1,169.1	1,156.7
Intangible assets, accumulated amortization	$ 844.4	$ 817.2

Consolidated Balance Sheets (Parenthetical) [Abstract]

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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- Definition

Amount of allowance for credit loss on accounts receivable, classified as current.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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