Segment Reporting (Reconciliation of Consolidated Segment Adjusted OIBDA) (Schedule) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Segment Reporting, Measurement Disclosures [Abstract]
Adjusted OIBDA from continuing operations	$ 1,183.3	$ 1,261.7
Share-based compensation expense	(67.3)	(42.7)
Depreciation and amortization	(939.6)	(1,040.7)
Impairment, restructuring and other operating items, net	(70.9)	(60.7)
Operating income	105.5	117.6
Interest expense	(367.3)	(375.3)
Realized and unrealized losses on derivative instruments, net	(82.8)	(211.3)
Foreign currency transaction gains (losses), net	138.6	(101.7)
Realized and unrealized losses due to changes in fair values of certain investments and debt, net	(8.2)	(57.2)
Share of results of affiliates, net	(70.9)	(36.5)
Other income, net	6.0	7.2
Loss from continuing operations before income taxes	$ (279.1)	$ (657.2)

Adjusted Operating Income (Loss) before Depreciation and Amortization

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Sum of operating profit and nonoperating income (expense) before income taxes.

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Realized And Unrealized Gains (Losses) Due To Changes In Fair Values of Certain Investments and Debt, Net

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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