Business Segment Information - Selected Financial Data for the Company's Business Segment Information (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Revenue		$ 276.4	$ 271.6
Operating income (loss)		10.7	(2.8)
Expenditures for long-lived assets	[1]	143.2	155.3
Depreciation and amortization		84.6	77.4
Operating Segments | Network [Member]
Segment Reporting Information [Line Items]
Revenue		276.4	271.6
Operating income (loss)		16.3	3.8
Expenditures for long-lived assets	[1]	140.4	155.3
Depreciation and amortization		84.6	77.4
Corporate [Member]
Segment Reporting Information [Line Items]
Operating income (loss)		(5.6)	(6.6)
Expenditures for long-lived assets	[1]	2.8	0.0
Depreciation and amortization		$ 0.0	$ 0.0

[1] Includes cost of acquisitions