Segment Reporting (Reconciliation of Operating Cash Flow to Earnings from Continuing Operations) (Schedule) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Share-based compensation expense	$ (33.4)	$ (39.0)
Depreciation and amortization	(232.2)	(222.7)
Impairment, restructuring and other operating items, net	1.7	(33.6)
Operating income (loss)	60.7	(12.3)
Interest expense	(127.5)	(145.5)
Realized and unrealized gains (losses) on derivative instruments, net	(164.7)	133.3
Foreign currency transaction gains (losses), net	(1,081.0)	559.3
Realized and unrealized gains due to changes in fair values of certain investments, net	55.8	113.1
Losses on debt extinguishment, net	(8.0)	0.0
Share of results of affiliates, net (note 5)	(148.0)	(7.0)
Other income, net	19.4	36.4
Earnings (loss) from continuing operations before income taxes	(1,393.3)	677.3
VMO2 JV And VodafoneZiggo JV
Segment Reporting Information [Line Items]
Adjusted EBITDA	1,536.5	1,592.6
VMO2 JV
Segment Reporting Information [Line Items]
Share of results of affiliates, net (note 5)	(86.6)	0.7
VodafoneZiggo JV
Segment Reporting Information [Line Items]
Share of results of affiliates, net (note 5)	(22.6)	6.6
Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	1,875.3	1,941.0
Operating Segments | VMO2 JV
Segment Reporting Information [Line Items]
Adjusted EBITDA	1,073.4	1,073.6
Operating Segments | VodafoneZiggo JV
Segment Reporting Information [Line Items]
Adjusted EBITDA	463.1	519.0
Operating Segments | Telenet
Segment Reporting Information [Line Items]
Adjusted EBITDA	301.6	308.4
Operating Segments | VM Ireland
Segment Reporting Information [Line Items]
Adjusted EBITDA	37.2	40.0
Intersegment Eliminations
Segment Reporting Information [Line Items]
Adjusted EBITDA	(10.0)	(34.7)
Central and Other
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 4.2	$ 30.7