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Investments in Qualified Affordable Housing Partnerships, Tax Credit and Other Investments, Net and Variable Interest Entities - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Dec. 31, 2023 | Dec. 31, 2022
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Minimum compliance period to fully utilize tax credits |  | 15 years |
Rayliant Global Advisors Limited |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Equity method investment, ownership (percent) | 49.99% |  |
Payments to acquire equity method investments | $ 95 |  |
Number of shares (in shares) | 349,138 |  |
Equity securities without readily determinable fair values |  | $ 101 |
Equity securities without readily determinable fair value, amount |  | 109 |
Rayliant Global Advisors Limited | Minimum | Performance Based Restricted Stock Units |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Percentage of target award available for grant | 20.00% |  |
Rayliant Global Advisors Limited | Maximum | Performance Based Restricted Stock Units |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Percentage of target award available for grant | 200.00% |  |
Investments in Qualified Affordable Housing Partnerships, Tax Credit and Other Investments, Net and Other Assets |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Equity securities with readily determinable fair value |  | 25 | $ 24
Equity securities without readily determinable fair value, amount |  | $ 146 | $ 37

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