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Derivative And Credit-Related Financial Instruments (Schedule Of Weighted Average Maturity And Interest Rates On Risk Management Cash Flow Swaps) (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Schedule of Weighted Average Maturity And Interest Rates On Risk Management Cash Flow Swaps [Line Items]
Notional/contract amount	$ 71,681	$ 67,665
Risk management purposes
Schedule of Weighted Average Maturity And Interest Rates On Risk Management Cash Flow Swaps [Line Items]
Notional/contract amount	31,962	30,142
Swaps - cash flow - receive fixed/pay floating rate | Risk management purposes | Forward Starting Swap | Derivatives designated as hedging instruments
Schedule of Weighted Average Maturity And Interest Rates On Risk Management Cash Flow Swaps [Line Items]
Notional/contract amount	$ 3,300	$ 4,600
Variable rate loans | Swaps - cash flow - receive fixed/pay floating rate | Risk management purposes | Cash flow swap
Schedule of Weighted Average Maturity And Interest Rates On Risk Management Cash Flow Swaps [Line Items]
Time to maturity (in years)	4 years 1 month 6 days	4 years 7 months 6 days
Receive rate	2.38%	2.35%
Pay rate	5.36%	4.07%

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- Definition

Schedule of Weighted Average Maturity And Interest Rates On Risk Management Cash Flow Swaps

+ References

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Average variable interest rate related to the group of interest rate derivatives.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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