CONSOLIDATED AND COMBINED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Statement [Abstract]
Revenues	$ 2,723.4	$ 2,696.4	$ 2,842.5
Costs and expenses:
Direct costs, exclusive of depreciation and amortization (including costs incurred from related parties of $48.8 during the year ended December 31, 2023)	2,219.6	2,162.2	2,251.9
Selling, general and administrative expenses, exclusive of depreciation and amortization	456.4	560.7	448.1
Depreciation and amortization	78.0	85.3	89.3
Goodwill and other asset impairments	797.9	0.0	0.0
Restructuring and other charges	44.1	50.1	21.2
Total costs and expenses	3,596.0	2,858.3	2,810.5
Operating (loss) income	(872.6)	(161.9)	32.0
Other income (expense):
Interest expense	(91.4)	(123.8)	(69.7)
Foreign exchange (loss) gain	(26.9)	(10.6)	0.3
Other, net	7.9	21.3	6.9
Loss from continuing operations before income taxes	(983.0)	(275.0)	(30.5)
Income tax expense (benefit)	3.2	(3.5)	1.2
Loss from continuing operations	(986.2)	(271.5)	(31.7)
(Loss) income from discontinued operations, net of tax	0.0	(57.0)	6.5
Net loss	$ (986.2)	$ (328.5)	$ (25.2)
Earnings (loss) per common share
Basic earnings (loss) per share from continued operations (in dollars per share)	$ (10.81)	$ (3.03)	$ (0.36)
Basic earnings (loss) per share from discontinued operations (in dollars per share)	0	(0.64)	0.07
Basic earnings (loss) per share (in dollars per share)	(10.81)	(3.67)	(0.29)
Diluted earnings (loss) per share from continuing operations (in dollars per share)	(10.81)	(3.03)	(0.36)
Diluted earnings (loss) per share from discontinued operations (in dollars per share)	0	(0.64)	0.07
Diluted earnings (loss) per share (in dollars per share)	$ (10.81)	$ (3.67)	$ (0.29)