Long-lived Assets (Schedule of Intangible Assets Subject to Amortization, Net) (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Gross carrying amount	$ 4,531.8	$ 4,572.9
Accumulated amortization	(3,338.6)	(2,964.4)
Net carrying amount	1,193.2	1,608.5
Customer relationships
Property, Plant and Equipment [Line Items]
Gross carrying amount	3,978.8	4,041.0
Accumulated amortization	(3,070.3)	(2,745.8)
Net carrying amount	908.5	1,295.2
Other
Property, Plant and Equipment [Line Items]
Gross carrying amount	553.0	531.9
Accumulated amortization	(268.3)	(218.6)
Net carrying amount	$ 284.7	$ 313.3