Debt (Capital Lease Obligations) (Schedule) (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Borrowings outstanding	$ 14,797.3	$ 14,559.6
2021 (remainder of year)	407.8
2022	539.9
2023	68.4
2024	28.0
2025	12.9
Total vendor financing maturities	14,797.3	14,559.6
Current portion	909.9
Noncurrent portion	13,824.7
UPC Holding
Debt Instrument [Line Items]
2021 (remainder of year)	143.1
2022	264.8
2023	0.0
2024	0.0
2025	0.0
Current portion	407.9
Noncurrent portion	7,281.8
Telenet
Debt Instrument [Line Items]
2021 (remainder of year)	221.4
2022	203.4
2023	11.7
2024	11.6
2025	11.6
Current portion	424.2
Noncurrent portion	5,372.8
Other
Debt Instrument [Line Items]
2021 (remainder of year)	43.3
2022	71.7
2023	56.7
2024	16.4
2025	1.3
Current portion	77.8
Noncurrent portion	111.6
Vendor financing
Debt Instrument [Line Items]
Borrowings outstanding	1,009.2	1,142.9
2021 (remainder of year)	406.9
2022	527.9
2023	56.7
2024	16.4
2025	1.3
Total vendor financing maturities	1,009.2	$ 1,142.9
Current portion	897.6
Noncurrent portion	111.6
Vendor financing \| UPC Holding
Debt Instrument [Line Items]
Borrowings outstanding	407.9
2021 (remainder of year)	143.1
2022	264.8
2023	0.0
2024	0.0
2025	0.0
Total vendor financing maturities	407.9
Current portion	407.9
Noncurrent portion	0.0
Vendor financing \| Telenet
Debt Instrument [Line Items]
Borrowings outstanding	411.9
2021 (remainder of year)	220.5
2022	191.4
2023	0.0
2024	0.0
2025	0.0
Total vendor financing maturities	411.9
Current portion	411.9
Noncurrent portion	0.0
Vendor financing \| Other
Debt Instrument [Line Items]
Borrowings outstanding	189.4
2021 (remainder of year)	43.3
2022	71.7
2023	56.7
2024	16.4
2025	1.3
Total vendor financing maturities	189.4
Current portion	77.8
Noncurrent portion	$ 111.6

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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