Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 43.4	$ 35.4
Property, plant and equipment, accumulated depreciation	$ 624.3	$ 553.8
Series A convertible preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	200,000,000	200,000,000
Series A convertible preferred stock, shares issued	1,027,689	1,027,689
Series A convertible preferred stock, shares outstanding	1,027,689	1,027,689
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,300,000,000	1,300,000,000
Common stock, shares issued	195,997,230	194,563,530
Common stock, shares outstanding	195,997,230	194,563,530
Treasury stock, shares	8,021,551	7,411,382

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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