Derivative Instruments (Cross-currency Derivative Contracts) (Details) - 9 months ended Sep. 30, 2020 € in Millions, zł in Millions, SFr in Millions, $ in Millions	CHF (SFr)	EUR (€)	USD ($)	PLN (zł)
UPC Holding | Cross-Currency Swap 1
Derivative [Line Items]
Weighted average remaining life	5 years
UPC Holding | Cross-Currency Swap 2
Derivative [Line Items]
Weighted average remaining life	5 years 8 months 12 days
UPC Holding | Cross-Currency Swap 3
Derivative [Line Items]
Weighted average remaining life	3 years 10 months 24 days
UPC Holding | Cross-Currency Swap 4
Derivative [Line Items]
Weighted average remaining life	3 years 7 months 6 days
UPC Holding | Cross-Currency Swap 5
Derivative [Line Items]
Weighted average remaining life	2 years 3 months 18 days
Telenet | Cross-Currency Swap 6
Derivative [Line Items]
Weighted average remaining life	6 years 3 months 18 days
Telenet | Cross-Currency Swap 7
Derivative [Line Items]
Weighted average remaining life	4 years 3 months 18 days
Due from Counterparty | UPC Holding | Cross-Currency Swap 1
Derivative [Line Items]
Notional amount of derivative | $			$ 360.0
Due from Counterparty | UPC Holding | Cross-Currency Swap 2
Derivative [Line Items]
Notional amount of derivative | $			1,600.0
Due from Counterparty | UPC Holding | Cross-Currency Swap 3
Derivative [Line Items]
Notional amount of derivative		€ 2,618.3
Due from Counterparty | UPC Holding | Cross-Currency Swap 4
Derivative [Line Items]
Notional amount of derivative		707.0
Due from Counterparty | UPC Holding | Cross-Currency Swap 5
Derivative [Line Items]
Notional amount of derivative | SFr	SFr 740.0
Due from Counterparty | Telenet | Cross-Currency Swap 6
Derivative [Line Items]
Notional amount of derivative | $			3,940.0
Due from Counterparty | Telenet | Cross-Currency Swap 7
Derivative [Line Items]
Notional amount of derivative		45.2
Due to Counterparty | UPC Holding | Cross-Currency Swap 1
Derivative [Line Items]
Notional amount of derivative		267.9
Due to Counterparty | UPC Holding | Cross-Currency Swap 2
Derivative [Line Items]
Notional amount of derivative | SFr	1,476.1
Due to Counterparty | UPC Holding | Cross-Currency Swap 3
Derivative [Line Items]
Notional amount of derivative | SFr	SFr 2,941.4
Due to Counterparty | UPC Holding | Cross-Currency Swap 4
Derivative [Line Items]
Notional amount of derivative | zł				zł 2,999.5
Due to Counterparty | UPC Holding | Cross-Currency Swap 5
Derivative [Line Items]
Notional amount of derivative		701.1
Due to Counterparty | Telenet | Cross-Currency Swap 6
Derivative [Line Items]
Notional amount of derivative		€ 3,489.6
Due to Counterparty | Telenet | Cross-Currency Swap 7
Derivative [Line Items]
Notional amount of derivative | $			$ 50.0