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Investment Securities - Narrative (Details) | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2025 USD ($) security | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) security | Sep. 30, 2024 USD ($) | Jun. 30, 2025 USD ($) | Dec. 31, 2024 USD ($) | Jun. 30, 2024 USD ($) | Dec. 31, 2023 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |
Available-for-sale securities, accrued interest receivable | $ 1,800,000 |  | $ 1,800,000 |  |  | $ 2,300,000 |  |
Held-to-maturity securities, accrued interest receivable | $ 1,800,000 |  | $ 1,800,000 |  |  | $ 1,800,000 |  |
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Other assets |  | Other assets |  |  | Other assets |  |
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Other assets |  | Other assets |  |  | Other assets |  |
Proceeds from sales of investment securities, available-for-sale | $ 73,400,000 | $ 7,900,000 | $ 73,400,000 | $ 25,600,000 |  |  |  |
Gross realized losses on securities | 1,000,000.0 | 454,000 | 1,000,000.0 | 1,400,000 |  |  |  |
Debt securities, available-for-sale, transfer in, allowance for credit loss, expense |  |  | 0 |  |  |  |  |
Debt securities, available-for-sale, allowance for credit loss | 0 |  | 0 |  |  |  |  |
Debt securities, held-to-maturity, credit loss expense (reversal) |  |  | 0 |  |  |  |  |
Debt securities, held-to-maturity, allowance for credit loss | $ 0 |  | $ 0 |  |  |  |  |
Number of available for sale securities that have unrealized losses | security | 200 |  | 200 |  |  |  |  |
Number of held to maturity securities that have unrealized losses | security | 147 |  | 147 |  |  |  |  |
Debt securities, available-for-sale, decline due to credit quality |  |  | $ 0 |  |  |  |  |
Allowance for credit losses | $ 18,086,000 | $ 19,663,000 | 18,086,000 | $ 19,663,000 | $ 19,153,000 | $ 18,980,000 | $ 18,806,000 | $ 18,371,000
Investment Securities |  |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |  |  |
Asset Pledged as Collateral |  |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |
Investment securities pledged as collateral | $ 388,200,000 |  | $ 388,200,000 |  |  | $ 451,500,000 |  |

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