Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Consolidated Balance Sheets (Parenthetical) [Abstract]
Allowance for doubtful accounts	$ 24.7	$ 32.1
Accumulated depreciation	1,275.8	1,279.2
Intangible assets, accumulated amortization	$ 727.1	$ 879.9

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.

+ References

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-Publisher FASB
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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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- Definition

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

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