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Variable Interest Entities - Schedule of Variable Interest Entities (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Variable Interest Entity [Line Items] |  |  |
Total assets | $ 213,758 | $ 109,298 | $ 58,309
Liabilities | 192,503 | 99,636 |
Variable Interest Entity, Not Primary Beneficiary |  |  |
Variable Interest Entity [Line Items] |  |  |
Total assets | 2,052 | 762 |
Amortization method qualified affordable housing project investments, tax provision | 169 | 60 | 22
Affordable housing tax credits and other tax benefits, amount | 176 | 77 | 26
Affordable housing tax credits, amount | 157 | 60 | $ 22
Variable Interest Entity, Not Primary Beneficiary | Total tax credit equity investments |  |  |
Variable Interest Entity [Line Items] |  |  |
Total assets | 1,890 | 603 |
Variable Interest Entity, Not Primary Beneficiary | Affordable housing tax credit investments |  |  |
Variable Interest Entity [Line Items] |  |  |
Total assets | 1,887 | 598 |
Variable Interest Entity, Not Primary Beneficiary | Other tax credit equity investments |  |  |
Variable Interest Entity [Line Items] |  |  |
Total assets | 3 | 5 |
Variable Interest Entity, Not Primary Beneficiary | Other unconsolidated investments |  |  |
Variable Interest Entity [Line Items] |  |  |
Total assets | 162 | 159 |
Variable Interest Entity, Not Primary Beneficiary | Commitments to tax credit investments |  |  |
Variable Interest Entity [Line Items] |  |  |
Liabilities | $ 947 | $ 295 |

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