Long-lived Assets (Intangible Assets Subject to Amortization, Net) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Gross carrying amount	$ 2,000.5	$ 1,914.8
Accumulated amortization	(670.4)	(624.4)
Net carrying amount	1,330.1	1,290.4
Licenses
Property, Plant and Equipment [Line Items]
Gross carrying amount	1,456.3	1,393.9
Accumulated amortization	(358.2)	(332.7)
Net carrying amount	1,098.1	1,061.2
Customer relationships
Property, Plant and Equipment [Line Items]
Gross carrying amount	266.8	255.4
Accumulated amortization	(171.8)	(161.0)
Net carrying amount	95.0	94.4
Other
Property, Plant and Equipment [Line Items]
Gross carrying amount	277.4	265.5
Accumulated amortization	(140.4)	(130.7)
Net carrying amount	$ 137.0	$ 134.8