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Investment Securities - Schedule Of Investments Within The Available For Sale Portfolio That Had Unrealized Losses (Details) - USD ($) $ in Millions | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Schedule of Investments [Line Items] |  |
Less than 12 months | $ 5,742 | $ 4,936
12 months or longer | 2,943 | 522
Total fair value | 8,685 | 5,458
Unrealized Losses |  |
Less than 12 months | (729) | (90)
12 months or longer | (645) | (22)
Total unrealized losses | (1,374) | (112)
Government agency issued MBS |  |
Schedule of Investments [Line Items] |  |
Less than 12 months | 3,168 | 2,973
12 months or longer | 1,517 | 184
Total fair value | 4,685 | 3,157
Unrealized Losses |  |
Less than 12 months | (429) | (41)
12 months or longer | (338) | (8)
Total unrealized losses | (767) | (49)
Government agency issued CMO |  |
Schedule of Investments [Line Items] |  |
Less than 12 months | 1,398 | 1,436
12 months or longer | 992 | 248
Total fair value | 2,390 | 1,684
Unrealized Losses |  |
Less than 12 months | (155) | (37)
12 months or longer | (205) | (10)
Total unrealized losses | (360) | (47)
Other U.S. government agencies |  |
Schedule of Investments [Line Items] |  |
Less than 12 months | 669 | 459
12 months or longer | 386 | 90
Total fair value | 1,055 | 549
Unrealized Losses |  |
Less than 12 months | (71) | (11)
12 months or longer | (85) | (4)
Total unrealized losses | (156) | (15)
States and municipalities |  |
Schedule of Investments [Line Items] |  |
Less than 12 months | 507 | 68
12 months or longer | 48 | 0
Total fair value | 555 | 68
Unrealized Losses |  |
Less than 12 months | (74) | (1)
12 months or longer | (17) | 0
Total unrealized losses | $ (91) | $ (1)

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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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI https://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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