Reportable Business Segments, Reconciliation of Segment Operating Income to Consolidated Income Before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information
Operating income	$ 464.8	$ 316.9
Stock-based compensation expense	(19.1)	(15.4)
Other operating expenses	(14.0)	(13.8)
Interest expense	(28.6)	(28.8)
Other (expense) income, net	(0.3)	1.1
Income before income taxes	435.9	289.2
Operating Segment
Segment Reporting Information
Operating income	$ 497.9	$ 346.1