Segment Reporting (Performance Measures) (Schedule) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Total consolidated revenue	$ 1,171.2	$ 1,091.3
Total reportable segment revenue	5,053.8	5,282.4
VMO2 JV And VodafoneZiggo JV
Segment Reporting Information [Line Items]
Total consolidated revenue	(4,178.3)	(4,396.8)
VMO2 JV
Segment Reporting Information [Line Items]
Total consolidated revenue		3,282.8
VodafoneZiggo JV
Segment Reporting Information [Line Items]
Total consolidated revenue		1,114.0
Telenet
Segment Reporting Information [Line Items]
Total consolidated revenue	759.7	762.6
VM Ireland
Segment Reporting Information [Line Items]
Total consolidated revenue	115.8	123.0
Reportable Segment
Segment Reporting Information [Line Items]
Total consolidated revenue	35.4	63.2
Operating Segments
Segment Reporting Information [Line Items]
Total reportable segment revenue	5,053.8	5,281.5
Operating Segments | VMO2 JV
Segment Reporting Information [Line Items]
Total consolidated revenue	3,126.3	3,282.8
Operating Segments | VodafoneZiggo JV
Segment Reporting Information [Line Items]
Total consolidated revenue	1,052.0	1,114.0
Operating Segments | Telenet
Segment Reporting Information [Line Items]
Total consolidated revenue	759.7	762.6
Operating Segments | VM Ireland
Segment Reporting Information [Line Items]
Total consolidated revenue	115.8	122.1
Intersegment Eliminations
Segment Reporting Information [Line Items]
Total reportable segment revenue	0.0	0.9
Intersegment Eliminations | Telenet
Segment Reporting Information [Line Items]
Total consolidated revenue	0.0	0.0
Intersegment Eliminations | VM Ireland
Segment Reporting Information [Line Items]
Total consolidated revenue	0.0	0.9
Central and Other
Segment Reporting Information [Line Items]
Total consolidated revenue	331.1	269.8
Central and Other | Related Party
Segment Reporting Information [Line Items]
Total consolidated revenue	161.1	32.2
Central and Other | JV Reportable Segments
Segment Reporting Information [Line Items]
Total consolidated revenue	134.6	174.4
Segments
Segment Reporting Information [Line Items]
Total consolidated revenue	$ (35.4)	$ (64.1)