Quarterly Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Revenues from services	[1]	$ 19,827.5	$ 20,724.4	$ 18,001.0
Gross profit		3,572.4	3,407.5	2,824.7
Operating profit (loss)		581.7	585.4	187.6
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest		$ 373.8	$ 382.4	$ 23.8
Net earnings (loss) per share - basic		$ 7.17	$ 7.01	$ 0.41
Net earnings (loss) per share - diluted		7.08	6.91	0.41
Dividends per share (in dollars per share)		$ 2.72	$ 2.52	$ 2.26

[1] (a) The United States revenues above represent revenues from our company-owned branches and franchise fees received from our franchise operations, which were $12.8, $12.8 and $12.6 for 2022, 2021 and 2020, respectively.