Investments (Equity Method Investments) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Schedule of Equity Method Investments [Line Items]
Equity method investment	$ (240.8)	$ 501.0	$ (341.1)	$ 812.6
VMO2 JV
Schedule of Equity Method Investments [Line Items]
Equity method investment	$ (198.0)	398.5	$ (187.6)	616.4
Percent of remaining results of operations included in investment	50.00%		50.00%
Percentage of share based compensation expense	100.00%		100.00%
VodafoneZiggo JV
Schedule of Equity Method Investments [Line Items]
Equity method investment	$ (9.7)	92.6	$ (97.6)	224.6
Percent of remaining results of operations included in investment	50.00%		50.00%
Percent of interest income earned on loan included in investment	100.00%		100.00%
Formula E
Schedule of Equity Method Investments [Line Items]
Equity method investment	$ (11.6)	(15.1)	$ (21.0)	(16.8)
AtlasEdge JV
Schedule of Equity Method Investments [Line Items]
Equity method investment	(4.8)	(5.2)	(15.2)	(13.3)
All3Media
Schedule of Equity Method Investments [Line Items]
Equity method investment	(7.8)	(10.2)	(6.1)	(27.1)
nexfibre JV
Schedule of Equity Method Investments [Line Items]
Equity method investment	(4.2)	41.6	2.1	41.6
Other, net
Schedule of Equity Method Investments [Line Items]
Equity method investment	$ (4.7)	$ (1.2)	$ (15.7)	$ (12.8)