Debt Obligations - Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument
Junior Subordinated Notes	$ 54	$ 54
Note payable to related company	550	732
Unamortized Net Premiums And Fair Value Adjustments	10	12
Total long-term debt outstanding	$ 245	247
8.125% Senior Notes due 2019
Debt Instrument
Debt Instrument, Interest Rate, Stated Percentage	8.125%
7.60% Senior Notes, due February 1, 2024 [Member]
Debt Instrument
Senior Notes	$ 82	82
Debt Instrument, Interest Rate, Stated Percentage	7.60%
Senior Notes Due 2029 [Member]
Debt Instrument
Senior Notes	$ 66	66
Debt Instrument, Interest Rate, Stated Percentage	7.00%
8.25% Senior Notes, due November 14, 2029 [Member]
Debt Instrument
Senior Notes	$ 33	$ 33
Debt Instrument, Interest Rate, Stated Percentage	8.25%
Panhandle [Member]
Debt Instrument
Junior Subordinated Notes	$ 600

Unamortized Net Premiums And Fair Value Adjustments

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Contractual interest rate for funds borrowed, under the debt agreement.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The amount for notes payable (written promise to pay), payable to related parties, which are due after one year (or one business cycle).

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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