Derivative Instruments (Interest Rate Swap Contracts and Options) (Details) - Interest Rate Swap $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($)
Due from Counterparty | UPC Holding
Derivative [Line Items]
Notional amount of derivative	$ 10,617.8
Weighted average remaining life	3 years 9 months 18 days
Due from Counterparty | Telenet
Derivative [Line Items]
Notional amount of derivative	$ 3,381.3
Weighted average remaining life	4 years 6 months
Due from Counterparty | Other
Derivative [Line Items]
Notional amount of derivative	$ 98.8
Weighted average remaining life	3 years 2 months 12 days
Due to Counterparty | UPC Holding
Derivative [Line Items]
Notional amount of derivative	$ 4,772.3
Weighted average remaining life	5 years 2 months 12 days
Due to Counterparty | Telenet
Derivative [Line Items]
Notional amount of derivative	$ 1,672.7
Weighted average remaining life	3 years