Debt (Maturities of Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
2020 (remainder of year)	$ 478.3
2021	1,471.3
2022	290.7
2023	172.7
2024	29.3
2025	13.4
Thereafter	9,053.6
Total debt maturities	11,509.3
Deferred financing costs, discounts and premiums, net	(43.3)
Total debt	11,466.0
Total vendor financing maturities	11,509.3	$ 27,648.1
Current portion	1,761.8
Noncurrent portion	9,704.2
Vendor financing
Debt Instrument [Line Items]
2020 (remainder of year)	366.8
2021	812.9
2022	85.0
2023	61.3
2024	16.7
2025	0.8
Total vendor financing maturities	1,343.5	1,374.3
Current portion	1,157.2
Noncurrent portion	186.3
ITV Collar Loan
Debt Instrument [Line Items]
Total vendor financing maturities	949.1	$ 1,435.5
UPC Holding
Debt Instrument [Line Items]
2020 (remainder of year)	209.1
2021	404.1
2022	0.0
2023	0.0
2024	0.0
2025	0.0
Thereafter	3,736.8
Total debt maturities	4,350.0
Deferred financing costs, discounts and premiums, net	(21.0)
Total debt	4,329.0
Current portion	613.2
Noncurrent portion	3,715.8
UPC Holding \| Vendor financing
Debt Instrument [Line Items]
2020 (remainder of year)	209.1
2021	404.1
2022	0.0
2023	0.0
2024	0.0
2025	0.0
Total vendor financing maturities	613.2
Current portion	613.2
Noncurrent portion	0.0
Telenet
Debt Instrument [Line Items]
2020 (remainder of year)	121.2
2021	295.8
2022	12.9
2023	12.6
2024	12.6
2025	12.8
Thereafter	5,316.8
Total debt maturities	5,784.7
Deferred financing costs, discounts and premiums, net	(17.7)
Total debt	5,767.0
Current portion	416.2
Noncurrent portion	5,350.8
Telenet \| Vendor financing
Debt Instrument [Line Items]
2020 (remainder of year)	121.0
2021	282.5
2022	0.0
2023	0.0
2024	0.0
2025	0.0
Total vendor financing maturities	403.5
Current portion	403.5
Noncurrent portion	0.0
Other
Debt Instrument [Line Items]
2020 (remainder of year)	148.0
2021	771.4
2022	277.8
2023	160.1
2024	16.7
2025	0.6
Thereafter	0.0
Total debt maturities	1,374.6
Deferred financing costs, discounts and premiums, net	(4.6)
Total debt	1,370.0
Current portion	732.4
Noncurrent portion	637.6
Other \| Vendor financing
Debt Instrument [Line Items]
2020 (remainder of year)	36.7
2021	126.3
2022	85.0
2023	61.3
2024	16.7
2025	0.8
Total vendor financing maturities	326.8
Current portion	140.5
Noncurrent portion	$ 186.3

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Long-term Debt, Gross Contractual Maturities

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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