Debt (Capital Lease Obligations) (Schedule) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
2021 (remainder of year)	$ 712.0
2022	440.1
2023	78.7
2024	30.4
2025	12.7
Total vendor financing maturities	13,889.8	$ 14,559.6
Current portion	986.3
Noncurrent portion	12,791.6
UPC Holding
Debt Instrument [Line Items]
2021 (remainder of year)	251.6
2022	124.0
2023	0.0
2024	0.0
2025	0.0
Current portion	375.6
Noncurrent portion	7,187.7
Telenet
Debt Instrument [Line Items]
2021 (remainder of year)	353.8
2022	84.3
2023	11.6
2024	11.5
2025	11.5
Current portion	426.0
Noncurrent portion	5,363.4
Other
Debt Instrument [Line Items]
2021 (remainder of year)	106.6
2022	231.8
2023	67.1
2024	18.9
2025	1.2
Current portion	184.7
Noncurrent portion	240.5
Vendor financing
Debt Instrument [Line Items]
2021 (remainder of year)	700.4
2022	289.7
2023	67.1
2024	18.9
2025	1.2
Total vendor financing maturities	1,077.3	$ 1,142.9
Current portion	930.0
Noncurrent portion	147.3
Vendor financing \| UPC Holding
Debt Instrument [Line Items]
2021 (remainder of year)	251.6
2022	124.0
2023	0.0
2024	0.0
2025	0.0
Total vendor financing maturities	375.6
Current portion	375.6
Noncurrent portion	0.0
Vendor financing \| Telenet
Debt Instrument [Line Items]
2021 (remainder of year)	342.2
2022	72.3
2023	0.0
2024	0.0
2025	0.0
Total vendor financing maturities	414.5
Current portion	414.5
Noncurrent portion	0.0
Vendor financing \| Other
Debt Instrument [Line Items]
2021 (remainder of year)	106.6
2022	93.4
2023	67.1
2024	18.9
2025	1.2
Total vendor financing maturities	287.2
Current portion	139.9
Noncurrent portion	$ 147.3

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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