CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 59.8	$ 67.9
Property, plant and equipment, accumulated depreciation	642.2	667.8
Intangible assets, accumulated amortization	$ 584.0	$ 584.9
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	120,000,000.0	120,000,000.0
Common stock, issued (in shares)	91,500,000	91,100,000
Common stock, outstanding (in shares)	91,500,000	91,100,000