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Investment Securities - Schedule of Amortized Cost, Unrealized Gains/(Losses) and Fair Value (Details) - USD ($) $ in Millions | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 10,092 |
Securities available for sale at fair value | 8,718 | $ 8,707
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 1,385 | 712
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (163) | (7)
Fair Value | 1,222 | 705
Government agency issued MBS |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 5,457 | 5,062
Gross Unrealized Gains | 0 | 42
Gross Unrealized Losses | (767) | (49)
Securities available for sale at fair value | 4,690 | 5,055
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 908 | 509
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (116) | (5)
Fair Value | 792 | 504
Government agency issued CMO |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 2,775 | 2,296
Gross Unrealized Gains | 0 | 8
Gross Unrealized Losses | (360) | (47)
Securities available for sale at fair value | 2,415 | 2,257
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 477 | 203
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (47) | (2)
Fair Value | 430 | 201
Other U.S. government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 1,212 | 861
Gross Unrealized Gains | 0 | 4
Gross Unrealized Losses | (156) | (15)
Securities available for sale at fair value | 1,056 | 850
States and municipalities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 648 | 535
Gross Unrealized Gains | 0 | 11
Gross Unrealized Losses | (91) | (1)
Securities available for sale at fair value | 557 | 545
Securities available-for-sale, excluding interest only strip |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 10,092 | 8,754
Gross Unrealized Gains | 0 | 65
Gross Unrealized Losses | (1,374) | (112)
Securities available for sale at fair value | 8,718 | 8,707
Securities available-for-sale, excluding interest only strip | Collateral Pledged |  |
Debt Securities, Available-for-sale [Line Items] |  |
Securities available for sale at fair value | $ 6,400 | $ 6,500

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
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