v3.10.0.1

Derivative Instruments (Interest Rate Swap Contracts and Options) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($)
Interest Rate Swaption 1 | Virgin Media
Derivative [Line Items]
Notional amount of derivative	$ 6,275.6
Weighted average remaining life	1 year 4 months 24 days
Weighted average strike rate	2.47%
Interest Rate Swaption 2 | Virgin Media
Derivative [Line Items]
Notional amount of derivative	$ 601.1
Weighted average remaining life	1 year 4 months 24 days
Weighted average strike rate	2.08%
Interest Rate Swaption | UPC Holding
Derivative [Line Items]
Notional amount of derivative	$ 1,328.3
Weighted average remaining life	18 days
Weighted average strike rate	1.22%
Notional amount due from counterparty | Interest Rate Swap | Virgin Media
Derivative [Line Items]
Notional amount of derivative	$ 18,625.7
Weighted average remaining life	3 years 7 months 6 days
Notional amount due from counterparty | Interest Rate Swap | UPC Holding
Derivative [Line Items]
Notional amount of derivative	$ 5,766.6
Weighted average remaining life	5 years 1 month 6 days
Notional amount due from counterparty | Interest Rate Swap | Telenet
Derivative [Line Items]
Notional amount of derivative	$ 3,686.4
Weighted average remaining life	5 years 6 months
Notional amount due to counterparty | Interest Rate Swap | Virgin Media
Derivative [Line Items]
Notional amount of derivative	$ 11,789.1
Weighted average remaining life	5 years 8 months 12 days
Notional amount due to counterparty | Interest Rate Swap | UPC Holding
Derivative [Line Items]
Notional amount of derivative	$ 3,408.3
Weighted average remaining life	7 years 3 months 18 days
Notional amount due to counterparty | Interest Rate Swap | Telenet
Derivative [Line Items]
Notional amount of derivative	$ 1,666.3
Weighted average remaining life	5 years 2 months 12 days

X

- Definition

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

+ References

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

+ Details

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X

- 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

No definition available.

+ Details

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X

- Definition

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

+ References

No definition available.

+ Details

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X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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X

- Details

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- Details

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- Details

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- Details

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- Details

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