Segment Reporting (Performance Measures) (Schedule) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Revenue	$ 7,195.7	$ 10,311.3	$ 11,545.4
Adjusted EBITDA	2,595.4	3,963.1	4,703.5
VMO2 JV
Segment Reporting Information [Line Items]
Revenue	12,857.2	8,522.9	0.0
Adjusted EBITDA	4,562.2	2,716.6	0.0
VodafoneZiggo JV
Segment Reporting Information [Line Items]
Revenue	4,284.6	4,824.2	4,565.4
Adjusted EBITDA	2,018.0	2,265.6	2,142.0
Operating Segments | Switzerland
Segment Reporting Information [Line Items]
Revenue	3,180.9	3,321.9	1,573.8
Adjusted EBITDA	1,137.8	1,208.7	693.8
Operating Segments | Belgium
Segment Reporting Information [Line Items]
Revenue	2,807.3	3,065.9	2,940.9
Adjusted EBITDA	1,308.1	1,481.8	1,413.4
Operating Segments | U.K.
Segment Reporting Information [Line Items]
Revenue	0.0	2,736.4	6,076.9
Adjusted EBITDA	0.0	1,085.3	2,453.5
Operating Segments | Ireland
Segment Reporting Information [Line Items]
Revenue	494.7	550.0	513.7
Adjusted EBITDA	197.5	218.6	202.0
Central and Other
Segment Reporting Information [Line Items]
Revenue	722.4	648.7	461.9
Adjusted EBITDA	(47.0)	(33.1)	(61.4)
Intersegment eliminations
Segment Reporting Information [Line Items]
Revenue	(9.6)	(11.6)	(21.8)
Adjusted EBITDA	$ (1.0)	$ 1.8	$ 2.2