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v3.24.2

Investment Securities - Additional Information (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 USD ($) security | Jun. 30, 2023 USD ($) | Jun. 30, 2024 USD ($) security | Jun. 30, 2023 USD ($) | Dec. 31, 2023 USD ($)
Summary of Investment Holdings [Line Items] |  |  |  |  |
Transferred from available-for-sale to held-for-maturity | $ 118,900,000 |  | $ 118,900,000 |  | $ 127,600,000
Allowance for credit losses for available-for-sale debt securities | $ 0 |  | $ 0 |  | $ 0
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest |  | Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest |  | Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest
Allowance for securities held-to-maturity | $ 150,000 |  | $ 150,000 |  | $ 150,000
Accrued interest receivable | $ 53,000,000.0 |  | $ 53,000,000.0 |  | 50,300,000
Number of securities in security portfolio | security | 3,039 |  | 3,039 |  |
Number of securities in unrealized loss position | security | 2,792 |  | 2,792 |  |
Equity securities, at fair value | $ 85,521,000 |  | $ 85,521,000 |  | 80,372,000
(Losses) gains on equity securities | (400,000) | $ 100,000 | (100,000) | $ (700,000) |
Impairments on equity securities without readily determinable fair value |  |  | 0 | 0 |
Downward adjustments on equity securities without readily determinable fair value |  |  | 0 | $ 0 |
Other Assets |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | 514,800,000 |  | 514,800,000 |  | $ 449,300,000
Other Assets | Partnership Interest |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | 274,900,000 |  | 274,900,000 |  |
Other Assets | Initiatives in Low-to-Moderate Income Neighborhoods |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | $ 239,900,000 |  | $ 239,900,000 |  |

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