Long-Term Debt and Credit Facilities - First Lien Note Refinancing (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Long-term debt
Net loss on early extinguishment of debt	$ 236,000,000	$ 0	$ 270,000,000	$ (54,000,000)
Senior notes | First Lien Notes
Long-term debt
Debt instrument, face amount	$ 2,000,000,000		$ 2,000,000,000
Stated interest rate	6.875%		6.875%
Amount outstanding	$ 4,087,000,000		$ 4,087,000,000		$ 3,846,000,000
Senior notes | First Lien Notes Refinancing
Long-term debt
Net loss on early extinguishment of debt	$ 236,000,000		$ 236,000,000
Senior notes | 10.500% First Lien Senior Secured Notes Due 2030
Long-term debt
Stated interest rate	10.50%		10.50%
Amount outstanding	$ 925,000,000		$ 925,000,000
Senior notes | 10.500% First Lien Notes Due 2029
Long-term debt
Stated interest rate	10.50%		10.50%
Amount outstanding	$ 668,000,000		$ 668,000,000
Senior notes | 11.000% First Lien Notes Due 2029
Long-term debt
Stated interest rate	11.00%		11.00%
Amount outstanding	$ 167,000,000		$ 167,000,000