Debt (Maturities of Debt) (Details) $ in Millions	Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
2021 (remainder of year)	$ 188.9
2022	753.6
2023	67.1
2024	27.5
2025	12.6
2026	11.5
Thereafter	13,589.7
Total debt maturities	14,650.9
Deferred financing costs, discounts and premiums, net	(60.3)
Total debt	14,590.6
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
2026	0.0
Thereafter	7,252.6
Total debt maturities	7,667.1
Deferred financing costs, discounts and premiums, net	(37.7)
Total debt	7,629.4
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
2026	11.5
Thereafter	5,295.8
Total debt maturities	5,773.4
Deferred financing costs, discounts and premiums, net	(15.1)
Total debt	5,758.3
Current portion	431.3
Noncurrent portion	5,327.0
VM Ireland
Debt Instrument [Line Items]
2021 (remainder of year)	0.0
2022	0.0
2023	0.0
2024	0.0
2025	0.0
2026	0.0
Thereafter	1,041.3
Total debt maturities	1,041.3
Deferred financing costs, discounts and premiums, net	(7.5)
Total debt	1,033.8
Current portion	0.0
Noncurrent portion	1,033.8
Other
Debt Instrument [Line Items]
2021 (remainder of year)	25.7
2022	70.4
2023	55.7
2024	16.1
2025	1.2
2026	0.0
Thereafter	0.0
Total debt maturities	169.1
Deferred financing costs, discounts and premiums, net	0.0
Total debt	169.1
Current portion	72.8
Noncurrent portion	$ 96.3

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

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