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Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024	Aug. 31, 2023	Jul. 31, 2023
Debt Instrument [Line Items]
Total principal debt	$ 625	$ 625
Premium on bond issuance	1	1
Total debt premium	1	1
Less: bond issuance costs	(14)	(16)
Total debt	612	610
Secured Debt
Debt Instrument [Line Items]
Total principal debt	575	575
Unsecured Debt
Debt Instrument [Line Items]
Total principal debt	50	50
Second Lien Facility \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, face amount	575		$ 75	$ 500
Total principal debt	575	575
Unsecured senior convertible bond \| Unsecured Debt
Debt Instrument [Line Items]
Total principal debt	$ 50	$ 50