Condensed Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Income Statement [Abstract]
Revenues	$ 159.0	$ 180.2	$ 313.0	$ 354.9
Costs and expenses:
Cost of sales	125.6	136.0	249.4	280.0
Depreciation and amortization	23.7	23.1	48.4	45.0
Selling, general and administrative	18.0	19.3	39.6	40.9
Research and development costs	0.4	0.3	0.8	0.6
Loss on debt extinguishment	0.0	0.0	1.2	0.0
Impairment and other charges	0.0	0.1	0.0	0.1
Operating (loss) income	(8.7)	1.4	(26.4)	(11.7)
Non-operating expense:
Interest income	(0.0)	(0.6)	(0.3)	(1.3)
Interest expense	11.0	9.8	21.3	19.4
Net loss before income tax	(19.7)	(7.8)	(47.4)	(29.8)
Income tax expense	0.2	0.2	0.4	0.4
Net loss	$ (19.9)	$ (8.0)	$ (47.8)	$ (30.2)
Net loss per share-basic (in dollars per share)	$ (1.04)	$ (0.49)	$ (2.63)	$ (1.86)
Net loss per share-diluted (in dollars per share)	$ (1.04)	$ (0.49)	$ (2.63)	$ (1.86)