Business Combinations - Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Summary of unaudited consolidated pro forma results of operations
Revenues	$ 6,989.5	$ 6,911.6	$ 21,242.8	$ 20,659.1
Income from continuing operations	340.3	363.0	1,086.9	904.1
Net income	$ 340.3	$ 363.2	$ 1,086.9	$ 904.5
Income from continuing operations per diluted common share (in dollars per share)	$ 4.61	$ 4.56	$ 14.38	$ 11.26
Net income per diluted common share (in dollars per share)	$ 4.61	$ 4.57	$ 14.38	$ 11.26