Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Income Statement [Abstract]
Revenue	$ 2,284.6	$ 2,184.8
Costs and expenses:
Costs of services (exclusive of depreciation and amortization)	1,900.3	1,832.5
Operating, administrative and other	305.8	296.0
Depreciation and amortization	26.7	32.5
Restructuring, impairment and related charges	6.5	5.0
Total costs and expenses	2,239.3	2,166.0
Operating income	45.3	18.8
Interest expense, net of interest income	(52.3)	(58.7)
Earnings from equity method investments	11.1	11.7
Other income, net	0.9	1.7
Earnings (loss) before income taxes	5.0	(26.5)
Provision for income taxes	3.1	2.3
Net income (loss)	$ 1.9	$ (28.8)
Basic earnings (loss) per share:
Earnings (loss) per share attributable to common shareholders, basic (in dollars per share)	$ 0.01	$ (0.13)
Weighted average shares outstanding for basic earnings (loss) per share (in dollars per share)	230.4	227.9
Diluted earnings (loss) per share:
Earnings (loss) per share attributable to common shareholders, diluted (in dollars per share)	$ 0.01	$ (0.13)
Weighted average shares outstanding for diluted earnings (loss) per share (in shares)	232.3	227.9