Share-Based Compensation - Schedule of Share-Based Compensation Costs Related to RSUs and PRSUs (Details) - RSUs and PRSUs - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total Share-based compensation expense	$ 3	$ 11	$ 14	$ 59
Cost of services, exclusive of depreciation and amortization
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total Share-based compensation expense	0	3	5	11
Selling, general and administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total Share-based compensation expense	$ 3	$ 8	$ 9	$ 48