Derivative Instruments (Interest Rate Swap Contracts, Options and Basis Swaps) (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)
Interest Rate Swaption 1 \| Virgin Media
Derivative [Line Items]
Notional amount of derivative	$ 6,062.5
Weighted average remaining life	27 days
Weighted average strike rate	2.47%
Interest Rate Swaption 2 \| Virgin Media
Derivative [Line Items]
Notional amount of derivative	$ 589.5
Weighted average remaining life	27 days
Weighted average strike rate	2.08%
Interest Rate Swaption \| UPC Holding
Derivative [Line Items]
Notional amount of derivative	$ 1,340.6
Weighted average remaining life	3 days
Weighted average strike rate	1.22%
Basis Swaps \| Virgin Media
Derivative [Line Items]
Weighted average remaining life	15 days
Basis Swaps \| UPC Holding
Derivative [Line Items]
Weighted average remaining life	12 days
Basis Swaps \| Telenet
Derivative [Line Items]
Weighted average remaining life	9 days
Due From Counterparty \| Interest Rate Swap \| Virgin Media
Derivative [Line Items]
Notional amount of derivative	$ 17,196.5
Weighted average remaining life	3 years 4 months 24 days
Due From Counterparty \| Interest Rate Swap \| UPC Holding
Derivative [Line Items]
Notional amount of derivative	$ 5,800.3
Weighted average remaining life	4 years 7 months 6 days
Due From Counterparty \| Interest Rate Swap \| Telenet
Derivative [Line Items]
Notional amount of derivative	$ 3,853.2
Weighted average remaining life	5 years 2 months 12 days
Due From Counterparty \| Basis Swaps \| Virgin Media
Derivative [Line Items]
Notional amount of derivative	$ 4,547.1
Due From Counterparty \| Basis Swaps \| UPC Holding
Derivative [Line Items]
Notional amount of derivative	2,640.0
Due From Counterparty \| Basis Swaps \| Telenet
Derivative [Line Items]
Notional amount of derivative	3,675.0
Due To Counterparty \| Interest Rate Swap \| Virgin Media
Derivative [Line Items]
Notional amount of derivative	$ 11,043.5
Weighted average remaining life	5 years 2 months 12 days
Due To Counterparty \| Interest Rate Swap \| UPC Holding
Derivative [Line Items]
Notional amount of derivative	$ 3,992.6
Weighted average remaining life	6 years 9 months 18 days
Due To Counterparty \| Interest Rate Swap \| Telenet
Derivative [Line Items]
Notional amount of derivative	$ 1,634.1
Weighted average remaining life	4 years 8 months 12 days

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Average fixed interest rate that will be received or paid upon exercise of a group of interest rate swaption contracts.

+ References

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- Definition

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