Share-based Compensation (Summary Of Stock-Based Compensation) (Schedule and Footnotes) (Details) In Millions, except Share data, unless otherwise specified	12 Months Ended																							12 Months Ended			12 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2014 Continuing operations [Member] USD ($)	Dec. 31, 2013 Continuing operations [Member] USD ($)	Dec. 31, 2012 Continuing operations [Member] USD ($)	Dec. 31, 2014 Discontinued operations [Member] USD ($)	Dec. 31, 2013 Discontinued operations [Member] USD ($)	Dec. 31, 2012 Discontinued operations [Member] USD ($)	Dec. 31, 2014 Operating Expense [Member] Continuing operations [Member] USD ($)	Dec. 31, 2013 Operating Expense [Member] Continuing operations [Member] USD ($)	Dec. 31, 2012 Operating Expense [Member] Continuing operations [Member] USD ($)	Dec. 31, 2014 Selling, General and Administrative Expenses [Member] Continuing operations [Member] USD ($)	Dec. 31, 2013 Selling, General and Administrative Expenses [Member] Continuing operations [Member] USD ($)	Dec. 31, 2012 Selling, General and Administrative Expenses [Member] Continuing operations [Member] USD ($)	Dec. 31, 2014 Liberty Global [Member] USD ($)	Dec. 31, 2013 Liberty Global [Member] USD ($)	Dec. 31, 2012 Liberty Global [Member] USD ($)	Dec. 31, 2013 Telenet [Member] USD ($)	Dec. 31, 2012 Telenet [Member] USD ($)	Dec. 31, 2014 Telenet [Member] Performance Shares [Member]	Dec. 31, 2014 Telenet [Member] Performance Shares [Member] Chief Executive Officer [Member] USD ($)	Dec. 31, 2014 Telenet [Member] Performance Shares [Member] Chief Executive Officer [Member] EUR (€)	Dec. 31, 2013 Telenet [Member] Options [Member] USD ($)	Dec. 31, 2014 Telenet [Member] Options [Member] USD ($)	Dec. 31, 2014 Telenet [Member] Options [Member] EUR (€)	Dec. 31, 2014 Performance-based incentive awards [Member] Liberty Global [Member] USD ($)	Dec. 31, 2013 Performance-based incentive awards [Member] Liberty Global [Member] USD ($)	Dec. 31, 2012 Performance-based incentive awards [Member] Liberty Global [Member] USD ($)	Dec. 31, 2014 Other share-based incentive awards [Member] Liberty Global [Member] USD ($)	Dec. 31, 2013 Other share-based incentive awards [Member] Liberty Global [Member] USD ($)	Dec. 31, 2012 Other share-based incentive awards [Member] Liberty Global [Member] USD ($)	Dec. 31, 2014 Share-based incentive awards [Member] Telenet [Member] USD ($)	Dec. 31, 2013 Share-based incentive awards [Member] Telenet [Member] USD ($)	Dec. 31, 2012 Share-based incentive awards [Member] Telenet [Member] USD ($)	Dec. 31, 2014 Other [Member] USD ($)	Dec. 31, 2013 Other [Member] USD ($)	Dec. 31, 2012 Other [Member] USD ($)	Dec. 31, 2014 Virgin Media Replacement Awards [Member] USD ($)	Dec. 31, 2013 Virgin Media Replacement Awards [Member] USD ($)	Dec. 31, 2014 Virgin Media Replacement Awards [Member] Operating Expense [Member] USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense	$ 257.2	$ 302.5	$ 112.4	$ 257.2	$ 300.7	$ 110.1	$ 0	$ 1.8	$ 2.3	$ 7.6	$ 12.1	$ 8.5	$ 249.6	$ 288.6	$ 101.6	$ 229.6	$ 241.5	$ 79.0	$ 32.7	$ 12.6				$ 6.2			$ 129.9	$ 58.6	$ 33.0	$ 99.7	$ 182.9	$ 46.0	$ 14.6	$ 56.5	$ 31.2	$ 13.0	$ 4.5	$ 2.2	$ 55.8	$ 134.3	$ 80.1
Awards outstanding (in shares)																					87,529	565,000	565,000		1,082,322	1,082,322
Awards outstanding (in EUR/USD per share)																						$ 45.29	€ 37.43		$ 32.88	€ 27.17