Long-Term Debt and Shareholders' Equity (Long-term Debt) (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Debt And Equity [Abstract]
Subordinated notes	$ 596	$ 619
Senior notes	708	713
Finance lease obligations	4	4
Total	$ 1,308	$ 1,336

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

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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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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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