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Derivative And Credit-Related Financial Instruments (Schedule Of Financial Instruments With Off-Balance Sheet Credit Risk) (Details) - Maximum - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
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Unused Commitments to Extend Credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | $ 28,506 | $ 28,397
Commercial and other | Unused Commitments to Extend Credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | 24,525 | 24,342
Bankcard, revolving credit and home equity loan commitments | Unused Commitments to Extend Credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | 3,981 | 4,055
Standby letters of credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | 4,181 | 4,138
Commercial letters of credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | $ 15 | $ 12

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- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 275 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482861/275-10-50-9 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 720 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483359/720-20-50-1 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 27 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482395/460-10-55-27 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-9 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-4 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482425/460-10-50-3 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482425/460-10-50-2 + Details
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