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v3.24.3

Investment Securities - Additional Information (Details) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 USD ($) security | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) security | Sep. 30, 2023 USD ($) | Dec. 31, 2023 USD ($)
Summary of Investment Holdings [Line Items] |  |  |  |  |
Transferred from available-for-sale to held-for-maturity | $ 114,200,000 |  | $ 114,200,000 |  | $ 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 | $ 42,500,000 |  | $ 42,500,000 |  | 50,300,000
Number of securities in security portfolio | security | 3,013 |  | 3,013 |  |
Number of securities in unrealized loss position | security | 2,452 |  | 2,452 |  |
Equity securities, at fair value | $ 89,249,000 |  | $ 89,249,000 |  | 80,372,000
(Losses) gains on equity securities | 1,500,000 | $ (800,000) | 1,400,000 | $ (1,400,000) |
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 | 580,300,000 |  | 580,300,000 |  | 449,300,000
Other Assets | Partnership Interest |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | 292,600,000 |  | 292,600,000 |  | 252,200,000
Other Assets | Initiatives in Low-to-Moderate Income Neighborhoods |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | $ 287,700,000 |  | $ 287,700,000 |  | $ 197,100,000

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