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Investment Securities - Schedule of Interest and Dividends on Investment Securities (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
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Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Investments [Abstract] |  |  |  |
Interest income - taxable investment securities | $ 89 | $ 39 | $ 260 | $ 104
Dividend income - marketable equity securities | 1 | 1 | 2 | 2
Interest on investment securities | $ 90 | $ 40 | $ 262 | $ 106

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- Definition Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.2) -URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1402 -Paragraph (a) Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1402 -Paragraph (b) -Subparagraph (1) + Details
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