Debt Obligations - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument
Debt Instrument, Fair Value Disclosure	$ 253	$ 256
Long term debt, amount outstanding	243	245
Note payable to related company	221	550
Junior Subordinated Notes	54	54
Unamortized Net Premiums And Fair Value Adjustments	$ 8	$ 10
3.26% Junior Subordinated Notes due November 1, 2066 [Member]
Debt Instrument
Debt Instrument, Interest Rate, Stated Percentage	3.0175%
Long-term Debt, Weighted Average Interest Rate, at Point in Time	3.149%	3.232%
8.125% Senior Notes due 2019
Debt Instrument
Debt Instrument, Interest Rate, Stated Percentage	8.125%
Senior Notes Due 2029 [Member]
Debt Instrument
Senior Notes	$ 66	$ 66
Debt Instrument, Interest Rate, Stated Percentage	7.00%
7.60% Senior Notes, due February 1, 2024 [Member]
Debt Instrument
Senior Notes	$ 82	82
Debt Instrument, Interest Rate, Stated Percentage	7.60%
8.25% Senior Notes, due November 14, 2029 [Member]
Debt Instrument
Senior Notes	$ 33	$ 33
Debt Instrument, Interest Rate, Stated Percentage	8.25%

Unamortized Net Premiums And Fair Value Adjustments

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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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- Definition

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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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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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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