Reportable Business Segments, Reconciliation of Segment Operating Income to Consolidated Income Before Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information
Operating income	$ 316.9	$ 376.2
Stock-based compensation expense	(15.4)	(14.4)
Acquisition-related expenses	0.0	(16.5)
Other operating expenses	(13.8)	(13.4)
Interest expense	(28.8)	(29.7)
Other income, net	1.1	3.0
Income before income taxes	289.2	349.5
Operating Segment
Segment Reporting Information
Operating income	$ 346.1	$ 420.5

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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