Debt and Capital Lease Obligations (Maturities of Debt) (Schedule) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
2019	$ 3,537.5
2020	269.8
2021	2,320.2
2022	673.3
2023	108.7
Thereafter	22,405.8
Total debt maturities	29,315.3
Deferred financing costs, discounts and premiums, net	(131.4)	$ (171.8)
Total debt	29,183.9
Total carrying amount of debt	29,183.9	$ 32,006.2
Current portion	3,537.0
Noncurrent portion	25,646.9
Virgin Media
Debt Instrument [Line Items]
2019	2,454.2
2020	15.7
2021	1,320.7
2022	314.1
2023	75.3
Thereafter	11,629.4
Total debt maturities	15,809.4
Deferred financing costs, discounts and premiums, net	(38.1)
Total debt	15,771.3
Current portion	2,454.2
Noncurrent portion	13,317.1
UPC Holding
Debt Instrument [Line Items]
2019	587.4
2020	24.3
2021	25.4
2022	24.1
2023	21.3
Thereafter	5,306.0
Total debt maturities	5,988.5
Deferred financing costs, discounts and premiums, net	(39.3)
Total debt	5,949.2
Current portion	587.4
Noncurrent portion	5,361.8
Telenet
Debt Instrument [Line Items]
2019	440.9
2020	16.9
2021	12.0
2022	11.9
2023	12.1
Thereafter	5,470.4
Total debt maturities	5,964.2
Deferred financing costs, discounts and premiums, net	(34.2)
Total debt	5,930.0
Current portion	440.9
Noncurrent portion	5,489.1
Other
Debt Instrument [Line Items]
2019	55.0
2020	212.9
2021	962.1
2022	323.2
2023	0.0
Thereafter	0.0
Total debt maturities	1,553.2
Deferred financing costs, discounts and premiums, net	(19.8)
Total debt	1,533.4
Current portion	54.5
Noncurrent portion	$ 1,478.9

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Long-term Debt, Gross Contractual Maturities

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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