Commitment and Contingencies MTA Agreement Schedule (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Change In MTA Deployment Costs Rollforward [Roll Forward]
Prepaid MTA equipment deployment costs, beginning of period	$ 0.0
Other current assets, beginning of period	11.1
Intangible assets, gross, beginning of period	2,465.3
MTA deployment costs, beginning of period	27.4	$ 11.9	$ 11.9
Deployment costs incurred	0.2	0.0
MTA equipment development cost additions	1.4		20.1
Total Recoupment And MTA Funding			(0.9)
Amortization	17.2	17.1
Prepaid MTA equipment deployment costs, end of period	0.2		0.0
Other current assets, end of period	11.6		11.1
Intangible assets, gross, end of period	2,429.8		2,465.3
MTA deployment costs, end of period	27.3		27.4
Franchise agreements
Change In MTA Deployment Costs Rollforward [Roll Forward]
Intangible assets, gross, beginning of period	909.0
Intangible assets, gross, end of period	866.6		909.0
MTA Funding
Change In MTA Deployment Costs Rollforward [Roll Forward]
Increase (Decrease) in Other Current Assets			(0.9)
MTA equipment deployment costs
Change In MTA Deployment Costs Rollforward [Roll Forward]
Other current assets, beginning of period	0.0	1.1	1.1
Increase (Decrease) in Other Current Assets			(0.2)
Amortization	(1.5)		(3.7)
Other current assets, end of period			0.0
MTA equipment deployment costs | Franchise agreements
Change In MTA Deployment Costs Rollforward [Roll Forward]
Intangible assets, gross, beginning of period	27.4	$ 10.8	10.8
Intangible asset related to franchise agreements additions	1.2		20.3
Amortization	(1.5)		(3.7)
Intangible assets, gross, end of period	$ 27.1		$ 27.4