Derivative Instruments (Realized and Unrealized Gains (Losses) on Derivatives) (Schedule and Footnotes) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Derivative [Line Items]
Gain (loss) on derivative instruments, net	$ (376.6)	$ 195.5
Cross-currency and interest rate derivative contracts
Derivative [Line Items]
Gain (loss) on derivative instruments, net	(420.2)	180.6
Foreign Exchange Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	20.0	102.4
Equity Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	24.1	(87.7)
Other
Derivative [Line Items]
Gain (loss) on derivative instruments, net	(0.5)	0.2
Sumitomo Collar [Member] | Equity Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	15.4	0
Ziggo Collar [Member] | Equity Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	8.5	(87.7)
Virgin Media Capped Call [Member] | Equity Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	$ 0.2	$ 0