Supplemental Cash Flow Data (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Change in Operating Capital [Abstract]
(Increase) decrease in accounts receivable	$ 1,095.5	$ 876.6
(Increase) decrease in work in process and other current assets	(55.3)	(115.0)
Increase (decrease) in accounts payable	(1,953.8)	(2,084.9)
Increase (decrease) in customer advances, taxes payable and other current liabilities	63.0	(14.1)
Change in other assets and liabilities, net	7.1	(11.8)
Use of operating capital	(843.5)	(1,349.2)
Income taxes paid	42.7	50.5
Interest paid	5.3	31.2
Operating leases, Net increase in lease liability	38.7	72.0
Finance leases, Net increase in lease liability	$ 11.7	$ 8.5