Segment Reporting (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue and Long-Lived Assets and Goodwill by Geographic Region
Revenue	$ 3,206.5	$ 3,623.8	$ 9,414.1	$ 10,812.5
Americas
Revenue and Long-Lived Assets and Goodwill by Geographic Region
Revenue	1,916.3	2,196.7	5,703.8	6,490.1
Long-lived assets and goodwill	7,632.5	7,844.6	7,632.5	7,844.6
EMEA
Revenue and Long-Lived Assets and Goodwill by Geographic Region
Revenue	920.2	1,008.2	2,661.2	3,129.6
Long-lived assets and goodwill	3,005.0	2,862.9	3,005.0	2,862.9
Asia-Pacific
Revenue and Long-Lived Assets and Goodwill by Geographic Region
Revenue	370.0	418.9	1,049.1	1,192.8
Long-lived assets and goodwill	$ 642.0	$ 632.0	$ 642.0	$ 632.0