Long-Term Debt and Credit Facilities - Schedule of Long Term Debt (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2024	Dec. 31, 2023
Long-term debt
Finance leases and other obligations	$ 238	$ 259
Unamortized (discounts) premiums, net	(233)	2
Unamortized debt issuance costs	(146)	(54)
Total long-term debt	10,202	8,983
Less current maturities	(35)	(31)
Long-term debt, excluding current maturities	$ 10,167	8,952
Term loan \| Term Loan B-1
Long-term debt
Basis spread on variable rate (as a percent)	6.56%
Long-term debt, gross	$ 1,199	0
Long-term debt, weighted average interest rate	11.838%
Term loan \| Term Loan B-2
Long-term debt
Basis spread on variable rate (as a percent)	6.56%
Long-term debt, gross	$ 1,199	0
Long-term debt, weighted average interest rate	11.838%
Term loan \| Former Facility
Long-term debt
Basis spread on variable rate (as a percent)	1.75%
Long-term debt, gross	$ 12	$ 2,411
Long-term debt, weighted average interest rate	7.111%	7.22%
Senior notes \| First Lien Notes
Long-term debt
Long-term debt, gross	$ 3,846	$ 925
Senior notes \| First Lien Notes \| Minimum
Long-term debt
Stated interest rate	10.50%
Senior notes \| First Lien Notes \| Maximum
Long-term debt
Stated interest rate	11.00%
Senior notes \| Second Lien Notes
Long-term debt
Long-term debt, gross	$ 2,579	0
Senior notes \| Second Lien Notes \| Minimum
Long-term debt
Stated interest rate	3.875%
Senior notes \| Second Lien Notes \| Maximum
Long-term debt
Stated interest rate	10.00%
Senior notes \| Former Senior Notes
Long-term debt
Long-term debt, gross	$ 0	1,500
Senior notes \| Former Senior Notes \| Minimum
Long-term debt
Stated interest rate	3.40%
Senior notes \| Former Senior Notes \| Maximum
Long-term debt
Stated interest rate	3.875%
Senior notes \| Senior Notes Maturing 2027-2029
Long-term debt
Long-term debt, gross	$ 1,508	$ 3,940
Senior notes \| Senior Notes Maturing 2027-2029 \| Minimum
Long-term debt
Stated interest rate	3.40%
Senior notes \| Senior Notes Maturing 2027-2029 \| Maximum
Long-term debt
Stated interest rate	4.625%
Senior notes \| 10.500% Senior Secured Notes Due 2030
Long-term debt
Stated interest rate		10.50%

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