Derivative Financial Instruments And Hedging Activities (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months		$ 427
Pre-tax net income related to amortization of discontinued cash flow hedges		174
Notional Amount	$ 126,602	126,602	$ 128,614
Maximum potential future exposure on swap participations	537	537
Aggregate fair value of all derivative instruments with credit risk	115	115	74
Posted collateral related to derivative instruments with credit risk	116	116	74
Not Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	104,352	104,352	104,764
Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	806	806	924
Forward Sale Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	1,500	1,500	1,900
Forward Rate Commitments and Futures Contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	3,900	3,900	$ 4,100
Interest Rate Floor [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value of terminated derivatives	250	2,300
Swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value of terminated derivatives	$ 3,000	$ 5,600

Notional Value of terminated derivatives

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-Section 50
-Paragraph 4H
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- Definition

Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions.

+ References

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

+ References

No definition available.

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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- Definition

The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994

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