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Debt Securities (Schedule Of Fair Value And Unrealized Losses Of Securities) (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
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Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 2,732 | $ 4,123
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (29) | (90)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 2,780 | 2,850
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (381) | (501)
Debt Securities, Available-for-sale, Unrealized Loss Position | 5,512 | 6,973
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (410) | (591)
U.S. Treasury and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 50 | 185
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | (3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 774 | 795
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (43) | (71)
Debt Securities, Available-for-sale, Unrealized Loss Position | 824 | 980
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (43) | (74)
Obligations of states and political subdivisions |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 110 | 539
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (1) | (8)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 222 | 225
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (17) | (24)
Debt Securities, Available-for-sale, Unrealized Loss Position | 332 | 764
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (18) | (32)
Mortgage-backed securities and collateralized mortgage obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 2,572 | 3,399
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (28) | (79)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,784 | 1,830
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (321) | (406)
Debt Securities, Available-for-sale, Unrealized Loss Position | 4,356 | 5,229
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | $ (349) | $ (485)

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479081/326-30-55-8 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-7 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-5 + Details
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