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Investments - Other Investments - Additional Information (Detail) | Dec. 31, 2022 USD ($) Investment Venture | Dec. 31, 2021 USD ($)
--- | --- | ---
Schedule of Equity Method Investments [Line Items] |  |
Non controlling interest certified low-income housing developments | Investment | 5 |
Liabilities | $ 29,717,600,000 | $ 24,784,900,000
Variable Interest Entity, Not Primary Beneficiary [Member] | Venture Capital Funds [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Liabilities | $ 400,000 |
Other Investments [Member] | One Startup Venture [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Non-controlling interest in startup venture number | Venture | 1 |
Assets | $ 2,200,000 |
Other Investments [Member] | Four Venture Capital Funds [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Assets | $ 3,400,000 |
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 | $ 4,600,000 |
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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