Debt (Capital Lease Obligations) (Schedule) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Borrowings outstanding	$ 14,650.9	$ 14,516.3
2021 (remainder of year)	188.9
2022	753.6
2023	67.1
2024	27.5
2025	12.6
Total vendor financing maturities	14,650.9	14,516.3
Current portion	918.6
Noncurrent portion	13,672.0
UPC Holding
Debt Instrument [Line Items]
2021 (remainder of year)	62.6
2022	351.9
2023	0.0
2024	0.0
2025	0.0
Current portion	414.5
Noncurrent portion	7,214.9
Telenet
Debt Instrument [Line Items]
2021 (remainder of year)	100.6
2022	331.3
2023	11.4
2024	11.4
2025	11.4
Current portion	431.3
Noncurrent portion	5,327.0
Other
Debt Instrument [Line Items]
2021 (remainder of year)	25.7
2022	70.4
2023	55.7
2024	16.1
2025	1.2
Current portion	72.8
Noncurrent portion	96.3
Vendor financing
Debt Instrument [Line Items]
Borrowings outstanding	1,003.5	1,099.6
2021 (remainder of year)	188.7
2022	741.8
2023	55.7
2024	16.1
2025	1.2
Total vendor financing maturities	1,003.5	$ 1,099.6
Current portion	907.2
Noncurrent portion	96.3
Vendor financing \| UPC Holding
Debt Instrument [Line Items]
Borrowings outstanding	414.5
2021 (remainder of year)	62.6
2022	351.9
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 \| Telenet
Debt Instrument [Line Items]
Borrowings outstanding	419.9
2021 (remainder of year)	100.4
2022	319.5
2023	0.0
2024	0.0
2025	0.0
Total vendor financing maturities	419.9
Current portion	419.9
Noncurrent portion	0.0
Vendor financing \| Other
Debt Instrument [Line Items]
Borrowings outstanding	169.1
2021 (remainder of year)	25.7
2022	70.4
2023	55.7
2024	16.1
2025	1.2
Total vendor financing maturities	169.1
Current portion	72.8
Noncurrent portion	$ 96.3

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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