Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Millions, $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Consolidated Balance Sheets (Parenthetical) [Abstract]
Allowance for doubtful accounts	$ 30.4	$ 21.5
Accumulated depreciation	1,156.7	1,142.8
Intangible assets, accumulated amortization	$ 817.2	$ 759.2
Preferred stock, par value	$ 1.00	$ 1.00
Preferred stock, shares authorized	7.5	7.5
Preferred stock, shares issued	0.0	0.0
Common stock, par value	$ 0.15	$ 0.15
Common stock, shares authorized	1,000.0	1,000.0
Common stock, shares issued	297.2	297.2
Common stock, shares outstanding	215.0	217.1
Treasury stock, shares	82.2	80.1