Derivative Instruments (Interest Rate Swaps) (Schedule) (Details) € in Millions, £ in Millions, SFr in Millions, $ in Millions	Dec. 31, 2016 EUR (€)	Dec. 31, 2016 USD ($)	Dec. 31, 2016 GBP (£)	Dec. 31, 2016 CHF (SFr)
Interest Rate Swap 1 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | $		$ 1,855.0
Interest Rate Swap 1 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative | $		2,150.0
Interest Rate Swap 1 [Member] | Unitymedia Hessen [Member]
Derivative [Line Items]
Notional amount of derivative	€ 268.2
Interest Rate Swap 1 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative | $		1,500.0
Interest Rate Swap 1 [Member] | Sable [Member]
Derivative [Line Items]
Notional amount of derivative | $		1,100.0
Interest Rate Swap 1 [Member] | Liberty Puerto Rico [Member]
Derivative [Line Items]
Notional amount of derivative | $		506.3
Interest Rate Swap 2 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | £			£ 1,198.3
Interest Rate Swap 2 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative | $		425.0
Interest Rate Swap 2 [Member] | Unitymedia Hessen [Member]
Derivative [Line Items]
Notional amount of derivative	268.2
Interest Rate Swap 2 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative	1,300.0
Interest Rate Swap 2 [Member] | Sable [Member]
Derivative [Line Items]
Notional amount of derivative | $		1,100.0
Interest Rate Swap 2 [Member] | Liberty Puerto Rico [Member]
Derivative [Line Items]
Notional amount of derivative | $		$ 168.8
Interest Rate Swap 3 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | £			905.1
Interest Rate Swap 3 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative	600.0
Interest Rate Swap 3 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative	1,093.0
Interest Rate Swap 4 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | £			858.3
Interest Rate Swap 4 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative	600.0
Interest Rate Swap 4 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative	800.0
Interest Rate Swap 5 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | £			849.4
Interest Rate Swap 5 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative | SFr				SFr 728.2
Interest Rate Swap 5 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative	557.0
Interest Rate Swap 6 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | £			628.4
Interest Rate Swap 6 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative | SFr				558.8
Interest Rate Swap 6 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative	475.0
Interest Rate Swap 7 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | £			340.0
Interest Rate Swap 7 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative | SFr				400.0
Interest Rate Swap 7 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative	420.0
Interest Rate Swap 8 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | £			108.9
Interest Rate Swap 8 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative | SFr				400.0
Interest Rate Swap 8 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative	382.0
Interest Rate Swap 9 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | £			51.5
Interest Rate Swap 9 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative | SFr				279.2
Interest Rate Swap 9 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative	55.0
Interest Rate Swap 10 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Notional amount of derivative | £			£ 33.3
Interest Rate Swap 10 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Notional amount of derivative | SFr				SFr 264.0
Interest Rate Swap 10 [Member] | Telenet International [Member]
Derivative [Line Items]
Notional amount of derivative	€ 32.0
Due From Counterparty [Member] | Interest Rate Swap 1 [Member] | Virgin Media Investment Holdings Limited [Member] | 1 mo. LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	2.75%	2.75%	2.75%	2.75%
Due From Counterparty [Member] | Interest Rate Swap 1 [Member] | UPC Broadband Holding [Member] | 1 mo. LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	3.00%	3.00%	3.00%	3.00%
Due From Counterparty [Member] | Interest Rate Swap 1 [Member] | Unitymedia Hessen [Member] | 6 mo. EURIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	4.82%	4.82%	4.82%	4.82%
Due From Counterparty [Member] | Interest Rate Swap 1 [Member] | Telenet International [Member] | 1 mo. LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	3.00%	3.00%	3.00%	3.00%
Due From Counterparty [Member] | Interest Rate Swap 1 [Member] | Sable [Member] | 1 mo. LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	4.75%	4.75%	4.75%	4.75%
Due From Counterparty [Member] | Interest Rate Swap 2 [Member] | UPC Broadband Holding [Member] | 6 mo. LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	5.76%	5.76%	5.76%	5.76%
Due From Counterparty [Member] | Interest Rate Swap 2 [Member] | Unitymedia Hessen [Member]
Derivative [Line Items]
Swap interest rate	5.02%	5.02%	5.02%	5.02%
Due From Counterparty [Member] | Interest Rate Swap 3 [Member] | Virgin Media Investment Holdings Limited [Member] | 6 mo. GBP LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	0.71%	0.71%	0.71%	0.71%
Due From Counterparty [Member] | Interest Rate Swap 3 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Swap interest rate	6.38%	6.38%	6.38%	6.38%
Due From Counterparty [Member] | Interest Rate Swap 4 [Member] | Telenet International [Member]
Derivative [Line Items]
Swap interest rate	0.17%	0.17%	0.17%	0.17%
Due From Counterparty [Member] | Interest Rate Swap 5 [Member] | Telenet International [Member]
Derivative [Line Items]
Swap interest rate	0.04%	0.04%	0.04%	0.04%
Due From Counterparty [Member] | Interest Rate Swap 6 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Swap interest rate	5.50%	5.50%	5.50%	5.50%
Due From Counterparty [Member] | Interest Rate Swap 8 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Swap interest rate	6.85%	6.85%	6.85%	6.85%
Due From Counterparty [Member] | Interest Rate Swap 9 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Swap interest rate	6.42%	6.42%	6.42%	6.42%
Due From Counterparty [Member] | Interest Rate Swap 9 [Member] | UPC Broadband Holding [Member] | 6 mo. CHF LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	2.85%	2.85%	2.85%	2.85%
Due From Counterparty [Member] | Interest Rate Swap 10 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Swap interest rate	0.65%	0.65%	0.65%	0.65%
Due To Counterparty [Member] | Interest Rate Swap 1 [Member] | Virgin Media Investment Holdings Limited [Member] | 6 mo. LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	2.74%	2.74%	2.74%	2.74%
Due To Counterparty [Member] | Interest Rate Swap 1 [Member] | UPC Broadband Holding [Member] | 6 mo. LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	2.56%	2.56%	2.56%	2.56%
Due To Counterparty [Member] | Interest Rate Swap 1 [Member] | Unitymedia Hessen [Member]
Derivative [Line Items]
Swap interest rate	5.01%	5.01%	5.01%	5.01%
Due To Counterparty [Member] | Interest Rate Swap 1 [Member] | Telenet International [Member] | 3 mo. LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	2.83%	2.83%	2.83%	2.83%
Due To Counterparty [Member] | Interest Rate Swap 1 [Member] | Sable [Member] | 3 mo. LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	4.68%	4.68%	4.68%	4.68%
Due To Counterparty [Member] | Interest Rate Swap 1 [Member] | Liberty Puerto Rico [Member]
Derivative [Line Items]
Swap interest rate	2.49%	2.49%	2.49%	2.49%
Due To Counterparty [Member] | Interest Rate Swap 2 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Swap interest rate	1.52%	1.52%	1.52%	1.52%
Due To Counterparty [Member] | Interest Rate Swap 2 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Swap interest rate	7.25%	7.25%	7.25%	7.25%
Due To Counterparty [Member] | Interest Rate Swap 2 [Member] | Unitymedia Hessen [Member] | 6 mo. EURIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	4.82%	4.82%	4.82%	4.82%
Due To Counterparty [Member] | Interest Rate Swap 2 [Member] | Telenet International [Member]
Derivative [Line Items]
Swap interest rate	0.33%	0.33%	0.33%	0.33%
Due To Counterparty [Member] | Interest Rate Swap 2 [Member] | Sable [Member]
Derivative [Line Items]
Swap interest rate	1.84%	1.84%	1.84%	1.84%
Due To Counterparty [Member] | Interest Rate Swap 2 [Member] | Liberty Puerto Rico [Member]
Derivative [Line Items]
Swap interest rate	1.96%	1.96%	1.96%	1.96%
Due To Counterparty [Member] | Interest Rate Swap 3 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Swap interest rate	2.37%	2.37%	2.37%	2.37%
Due To Counterparty [Member] | Interest Rate Swap 3 [Member] | UPC Broadband Holding [Member] | 6 mo. EURIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	4.14%	4.14%	4.14%	4.14%
Due To Counterparty [Member] | Interest Rate Swap 3 [Member] | Telenet International [Member]
Derivative [Line Items]
Swap interest rate	1.09%	1.09%	1.09%	1.09%
Due To Counterparty [Member] | Interest Rate Swap 4 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Swap interest rate	2.41%	2.41%	2.41%	2.41%
Due To Counterparty [Member] | Interest Rate Swap 4 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Swap interest rate	1.54%	1.54%	1.54%	1.54%
Due To Counterparty [Member] | Interest Rate Swap 5 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Swap interest rate	1.70%	1.70%	1.70%	1.70%
Due To Counterparty [Member] | Interest Rate Swap 5 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Swap interest rate	1.75%	1.75%	1.75%	1.75%
Due To Counterparty [Member] | Interest Rate Swap 6 [Member] | Virgin Media Investment Holdings Limited [Member] | 6 mo. GBP LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	1.84%	1.84%	1.84%	1.84%
Due To Counterparty [Member] | Interest Rate Swap 6 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Swap interest rate	0.93%	0.93%	0.93%	0.93%
Due To Counterparty [Member] | Interest Rate Swap 6 [Member] | Telenet International [Member]
Derivative [Line Items]
Swap interest rate	0.94%	0.94%	0.94%	0.94%
Due To Counterparty [Member] | Interest Rate Swap 7 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Swap interest rate	2.43%	2.43%	2.43%	2.43%
Due To Counterparty [Member] | Interest Rate Swap 7 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Swap interest rate	0.02%	0.02%	0.02%	0.02%
Due To Counterparty [Member] | Interest Rate Swap 7 [Member] | Telenet International [Member]
Derivative [Line Items]
Swap interest rate	2.08%	2.08%	2.08%	2.08%
Due To Counterparty [Member] | Interest Rate Swap 8 [Member] | Virgin Media Investment Holdings Limited [Member] | 6 mo. GBP LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	5.62%	5.62%	5.62%	5.62%
Due To Counterparty [Member] | Interest Rate Swap 8 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Swap interest rate	0.40%	0.40%	0.40%	0.40%
Due To Counterparty [Member] | Interest Rate Swap 8 [Member] | Telenet International [Member]
Derivative [Line Items]
Swap interest rate	1.89%	1.89%	1.89%	1.89%
Due To Counterparty [Member] | Interest Rate Swap 9 [Member] | Virgin Media Investment Holdings Limited [Member] | 6 mo. GBP LIBOR [Member]
Derivative [Line Items]
Basis spread on derivative variable rate	5.23%	5.23%	5.23%	5.23%
Due To Counterparty [Member] | Interest Rate Swap 9 [Member] | UPC Broadband Holding [Member]
Derivative [Line Items]
Swap interest rate	3.13%	3.13%	3.13%	3.13%
Due To Counterparty [Member] | Interest Rate Swap 9 [Member] | Telenet International [Member]
Derivative [Line Items]
Swap interest rate	1.81%	1.81%	1.81%	1.81%
Due To Counterparty [Member] | Interest Rate Swap 10 [Member] | Virgin Media Investment Holdings Limited [Member]
Derivative [Line Items]
Swap interest rate	1.37%	1.37%	1.37%	1.37%
Due To Counterparty [Member] | Interest Rate Swap 10 [Member] | Telenet International [Member]
Derivative [Line Items]
Swap interest rate	1.10%	1.10%	1.10%	1.10%