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v3.25.3

Investment Securities - Additional Information (Details) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 USD ($) security | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) security | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Summary of Investment Holdings [Line Items] |  |  |  |  |
Transferred from available-for-sale to held-for-maturity | $ 97,900,000 |  | $ 97,900,000 |  | $ 110,000,000.0
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 | $ 58,600,000 |  | $ 58,600,000 |  | 55,300,000
Number of securities in security portfolio | security | 3,197 |  | 3,197 |  |
Number of securities in unrealized loss position | security | 2,292 |  | 2,292 |  |
Equity securities, at fair value | $ 126,281,000 |  | $ 126,281,000 |  | 91,996,000
Gains on equity securities | 1,000,000.0 | $ 1,500,000 | 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 | 942,100,000 |  | 942,100,000 |  | 609,200,000
Other Assets | Partnership Interest |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | 553,700,000 |  | 553,700,000 |  | 318,500,000
Other Assets | Initiatives in Low-to-Moderate Income Neighborhoods |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Equity securities without readily determinable fair value | $ 388,300,000 |  | $ 388,300,000 |  | $ 290,700,000

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