Debt ( Component of Debt-Footnotes) (Details)	2 Months Ended		3 Months Ended
	Feb. 29, 2024 USD ($)	Feb. 29, 2024 EUR (€)	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2024 EUR (€)	Feb. 29, 2024 EUR (€)	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Weighted average interest rate			6.09%		6.09%
Unused borrowing capacity, amount			$ 1,535,400,000
Repayment of debt			5,900,000	$ 6,700,000
Deferred liabilities			410,900,000				$ 430,800,000
Long-term Debt
Debt Instrument [Line Items]
Estimated fair value			$ 15,200,000,000				$ 15,500,000,000
Aggregate Variable and Fixed Rate Indebtedness
Debt Instrument [Line Items]
Weighted average interest rate			3.41%		3.41%
Sunrise Holding Bank Facility
Debt Instrument [Line Items]
Weighted average interest rate			7.70%		7.70%
Unused borrowing capacity, amount			$ 763,400,000		€ 707,000,000
Sunrise Holding Bank Facility | Sunrise Holding Revolving Facility
Debt Instrument [Line Items]
Unused borrowing capacity, amount			763,400,000		707,000,000.0
Unused borrowing capacity, amount under covenant			763,400,000		707,000,000.0
Available to loan or distribute			763,400,000		707,000,000.0
Sunrise Holding Bank Facility | Debt Covenant, Scenario 1 | Sunrise Holding Revolving Facility
Debt Instrument [Line Items]
Unused borrowing capacity, amount			763,400,000		707,000,000.0
Available to loan or distribute			763,400,000		707,000,000.0
Sunrise Holding Revolving Facility B
Debt Instrument [Line Items]
Unused borrowing capacity, amount			752,600,000		697,000,000
Maximum borrowing capacity			777,400,000		720,000,000
Sunrise Holding Revolving Facility A
Debt Instrument [Line Items]
Unused borrowing capacity, amount	$ 64,800,000		10,800,000		10,000,000	€ 60,000,000
Maximum borrowing capacity | €					10,000,000
Sunrise Holding Revolving Facility Auxillary
Debt Instrument [Line Items]
Unused borrowing capacity, amount			24,800,000		23,000,000
Maximum borrowing capacity | €						60,000,000
Sunrise Holding Revolving Facility
Debt Instrument [Line Items]
Repayment of debt	19,400,000	€ 18,000,000
Sunrise Holding Revolving Facility One
Debt Instrument [Line Items]
Maximum borrowing capacity	788,200,000					730,000,000
Sunrise Holding Revolving Facility B, Auxillary
Debt Instrument [Line Items]
Maximum borrowing capacity | €					60,000,000
Telenet Revolving Credit Facility B
Debt Instrument [Line Items]
Unused borrowing capacity, amount			615,400,000		570,000,000
Telenet Revolving Credit Facility A
Debt Instrument [Line Items]
Unused borrowing capacity, amount	$ 32,400,000					€ 30,000,000
Telenet Overdraft Facility
Debt Instrument [Line Items]
Unused borrowing capacity, amount			27,000,000		25,000,000
Telenet Revolving Facility
Debt Instrument [Line Items]
Unused borrowing capacity, amount			$ 21,600,000		€ 20,000,000
VM Ireland Credit Facility
Debt Instrument [Line Items]
Weighted average interest rate			7.36%		7.36%
Unused borrowing capacity, amount			$ 108,000,000		€ 100,000,000
VM Ireland Credit Facility | Sunrise Holding Revolving Facility
Debt Instrument [Line Items]
Unused borrowing capacity, amount			108,000,000.0		100,000,000.0
Unused borrowing capacity, amount under covenant			108,000,000.0		100,000,000.0
Available to loan or distribute			108,000,000.0		100,000,000.0
VM Ireland Credit Facility | Debt Covenant, Scenario 1 | Sunrise Holding Revolving Facility
Debt Instrument [Line Items]
Unused borrowing capacity, amount			108,000,000.0		100,000,000.0
Available to loan or distribute			$ 108,000,000.0		€ 100,000,000.0
Vendor financing
Debt Instrument [Line Items]
Weighted average interest rate			4.97%		4.97%
Operating-related vendor financing additions			$ 159,800,000	$ 141,400,000
Telenet Credit Facility
Debt Instrument [Line Items]
Weighted average interest rate			6.95%		6.95%
Telenet Credit Facility | Sunrise Holding Revolving Facility
Debt Instrument [Line Items]
Unused borrowing capacity, amount			$ 664,000,000.0		€ 615,000,000.0
Unused borrowing capacity, amount under covenant			664,000,000.0		615,000,000.0
Available to loan or distribute			664,000,000.0		615,000,000.0
Telenet Credit Facility | Debt Covenant, Scenario 1 | Sunrise Holding Revolving Facility
Debt Instrument [Line Items]
Unused borrowing capacity, amount			664,000,000.0		615,000,000.0
Available to loan or distribute			$ 664,000,000.0		€ 615,000,000.0