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Investments - Other Investments - Additional Information (Detail) | Dec. 31, 2023 USD ($) Investment Venture | Dec. 31, 2022 USD ($)
--- | --- | ---
Schedule of Equity Method Investments [Line Items] |  |
Non controlling interest certified low-income housing developments | Investment | 5 |
Total liabilities | $ 40,800,500,000 | $ 29,168,200,000
Variable Interest Entity, Not Primary Beneficiary [Member] | Venture Capital Funds [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Total liabilities | $ 600,000 |
Other Investments [Member] | Startup Venture [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Non-controlling interest in startup venture number | Venture | 2 |
Assets | $ 7,100,000 |
Other Investments [Member] | Four Venture Capital Funds [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Assets | $ 3,200,000 |
Non controlling interest in venture capital funds number | Venture | 4 |
Other Investments [Member] | Variable Interest Entity, Not Primary Beneficiary [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Assets | $ 4,400,000 |
Other Investments [Member] | Variable Interest Entity, Not Primary Beneficiary [Member] | Five Certified Low-income Housing Developments [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Carrying value of investments | $ 0 |

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