Derivative Instruments (Impact of Derivative Instruments on Borrowing Costs) (Details)	Mar. 31, 2017
Virgin Media [Member]
Derivative [Line Items]
Impact of derivative instruments on borrowing costs	0.11%
Telenet [Member]
Derivative [Line Items]
Impact of derivative instruments on borrowing costs	(0.16%)
Unitymedia [Member]
Derivative [Line Items]
Impact of derivative instruments on borrowing costs	(0.29%)
UPC Holding [Member]
Derivative [Line Items]
Impact of derivative instruments on borrowing costs	0.43%
CWC [Member]
Derivative [Line Items]
Impact of derivative instruments on borrowing costs	0.45%
VTR Finance [Member]
Derivative [Line Items]
Impact of derivative instruments on borrowing costs	(0.52%)
Liberty Puerto Rico [Member]
Derivative [Line Items]
Impact of derivative instruments on borrowing costs	0.96%