Debt (Schedule Of Changes In Debt) (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Balance as of beginning-of-year	$ 6,682
Notes issued		$ 1,289
Repayment of notes		$ (1,096)
Unamortized debt issuance costs	3
Unamortized adjustments from discontinued hedges	(11)
Fair value hedge on interest rate swap agreements	(51)
Balance as of end-of-period	6,623
LIBOR + 236 bps, due 2066 [Member]
Debt Instrument [Line Items]
Capital securities exchanged	(562)
Notes issued	$ 562
LIBOR + 236 bps, due 2066 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	2.36%
LIBOR + 204 bps, due 2067 [Member]
Debt Instrument [Line Items]
Capital securities exchanged	$ (433)
Notes issued	$ 433
LIBOR + 204 bps, due 2067 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	2.04%

Gain (loss) on fair value hedge, Interest rate swap

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- Definition

Increase (Decrease) in Long-Term Debt, Long-term Debt Reclassified to Current

+ References

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- Definition

Unamortized adjustments from discontinued hedges

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- Definition

Unamortized debt issuance cost, change during the period

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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