Long-Term Debt and Note Payable - Affiliate - Schedule of Long Term Debt (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Long-term debt
Unamortized premiums, net	$ 5	$ 0
Unamortized debt issuance costs	(88)	(115)
Total long-term debt	4,127	5,951
Less current maturities	(1)	(1,105)
Long-term debt, excluding current maturities	4,126	4,846
Note payable - affiliate	1,130	1,069
Senior notes
Long-term debt
Long-term debt, gross	$ 4,105	5,956
Senior notes \| Minimum
Long-term debt
Stated interest rate	6.125%
Senior notes \| Maximum
Long-term debt
Stated interest rate	7.75%
Term loan
Long-term debt
Long-term debt, gross	$ 100	$ 100
Weighted average interest rate	2.15%	3.80%
Term loan \| London Interbank Offered Rate (LIBOR)
Long-term debt
Basis spread on variable rate	2.00%
Finance lease and other obligations
Long-term debt
Long-term debt, gross	$ 5	$ 10
Note payable - affiliate \| Affiliated entity
Long-term debt
Note payable - affiliate	$ 1,130	$ 1,069
Weighted average interest rate	4.974%

Amount of short-term and long-term debt and lease obligation.

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