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DEBT - Summary of Debt Obligations (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2025	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2022
Line of Credit Facility [Line Items]
Total debt obligations		$ 2,776	$ 2,776
Less: unamortized deferred financing costs		(18)	(23)
Total debt, net of deferred financing costs		2,758	2,753
Short-term and current portion of long-term debt		(5)	(4)
Long-term debt, less current portion		2,753	2,749
Term loan facility
Line of Credit Facility [Line Items]
Total debt obligations		2,157
Term loan facility \| 2021 Term Loan
Line of Credit Facility [Line Items]
Total debt obligations		2,157	2,157
Term loan facility \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Total debt obligations		$ 0	0
4.125% Senior Notes
Line of Credit Facility [Line Items]
Line of credit facility, interest rate	4.125%	4.125%		4.125%
Total debt obligations		$ 337	$ 337
4.750% Senior Notes
Line of Credit Facility [Line Items]
Line of credit facility, interest rate	4.75%	4.75%	4.75%	4.75%
Total debt obligations		$ 277	$ 277
Other obligations
Line of Credit Facility [Line Items]
Total debt obligations		$ 5	$ 5