Segment Reporting (Capital Expenditures of Reportable Segments) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Total property and equipment additions	$ 389.9	$ 381.9
Assets acquired under capital-related vendor financing arrangements	(42.3)	(66.7)
Assets acquired under finance leases	(7.3)	(8.7)
Changes in current liabilities related to capital expenditures	36.9	66.3
Total capital expenditures, net	377.2	372.8
VMO2 JV
Segment Reporting Information [Line Items]
Property and equipment additions:	590.6	659.3
VodafoneZiggo JV
Segment Reporting Information [Line Items]
Property and equipment additions:	250.4	220.4
Operating Segments | Switzerland
Segment Reporting Information [Line Items]
Total property and equipment additions	149.0	149.3
Operating Segments | Belgium
Segment Reporting Information [Line Items]
Total property and equipment additions	173.0	158.5
Operating Segments | Ireland
Segment Reporting Information [Line Items]
Total property and equipment additions	33.1	29.2
Central and Other
Segment Reporting Information [Line Items]
Total property and equipment additions	49.8	60.6
Intersegment eliminations
Segment Reporting Information [Line Items]
Total property and equipment additions	$ (15.0)	$ (15.7)