Long-Term Debt and Shareholders' Equity (Long-term Debt) (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2022	Dec. 31, 2021
Debt And Equity [Abstract]
Subordinated notes	$ 540	$ 590
Senior notes	127	418
Finance lease obligations	4	4
Total	671	$ 1,012
Debt Instrument [Line Items]
Amount change	$ (341)
Percent change	(34.00%)
Subordinated notes
Debt Instrument [Line Items]
Amount change	$ (50)
Percent change	(8.00%)
Senior notes
Debt Instrument [Line Items]
Amount change	$ (291)
Percent change	(70.00%)
Finance lease obligations
Debt Instrument [Line Items]
Amount change	$ 0
Percent change	0.00%

Net increase or decrease in the carrying amount of the debt instrument for the period.

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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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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Including the current and noncurrent portions, 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). Senior note holders are paid off in full before any payments are made to junior note holders.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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Debt And Equity

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Debt Instrument, Increase (Decrease), Net, Percentage

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