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Investment Securities - Schedule of Other Interest and Dividend Income (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Investments [Abstract] |  |
Interest on investment securities | $ 83 | $ 30
Interest income - interest-bearing cash | 5 | 1
Dividend income - marketable equity securities | 1 | 1
Total other interest and dividend income | $ 89 | $ 32

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