Derivative Instruments (Realized and Unrealized Gains (Losses) on Derivatives) (Schedule and Footnotes) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Derivative [Line Items]
Gain (loss) on derivative instruments, net	$ (328.6)	$ (3.4)	$ (705.2)	$ 192.1
Cross-currency and interest rate derivative contracts
Derivative [Line Items]
Gain (loss) on derivative instruments, net	(285.7)	162.4	(705.9)	343.0
Foreign Exchange Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	0.4	(103.5)	20.4	(1.1)
Equity Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	(44.4)	(61.8)	(20.3)	(149.5)
Other
Derivative [Line Items]
Gain (loss) on derivative instruments, net	1.1	(0.5)	0.6	(0.3)
Sumitomo Collar [Member] | Equity Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	(23.8)	(52.4)	(15.3)	(140.1)
Ziggo Collar [Member] | Equity Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	(21.3)	0	(5.9)	0
Virgin Media Capped Call [Member] | Equity Contract [Member]
Derivative [Line Items]
Gain (loss) on derivative instruments, net	$ 0.7	$ (9.4)	$ 0.9	$ (9.4)