Derivative Instruments (Impact of Derivative Instruments on Borrowing Costs) (Details)	Dec. 31, 2019
Derivative [Line Items]
Increase (decrease) to borrowing costs	(0.27%)
Virgin Media
Derivative [Line Items]
Increase (decrease) to borrowing costs	(0.20%)
UPC Holding
Derivative [Line Items]
Increase (decrease) to borrowing costs	(0.15%)
Telenet
Derivative [Line Items]
Increase (decrease) to borrowing costs	(0.58%)

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.

No definition available.

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