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Investment Securities - Narrative (Details) | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2024 USD ($) security | Jun. 30, 2024 USD ($) security | Jun. 30, 2023 USD ($) | Mar. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |
Available-for-sale securities, accrued interest receivable | $ 2,200,000 | $ 2,200,000 |  |  | $ 2,400,000 |  |
Held-to-maturity securities, accrued interest receivable | $ 1,900,000 | $ 1,900,000 |  |  | $ 1,900,000 |  |
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 | $ 9,200,000 | $ 17,750,000 | $ 0 |  |  |  |
Gross realized losses on securities | $ 425,000 | $ 980,000 |  |  |  |  |
Number of available for sale securities that have unrealized losses | security | 261 | 261 |  |  |  |  |
Number of held to maturity securities that have unrealized losses | security | 155 | 155 |  |  |  |  |
Allowance for credit loss | $ 18,806,000 | $ 18,806,000 | $ 17,066,000 | $ 18,657,000 | $ 18,371,000 | $ 16,599,000 | $ 16,128,000
Investment Securities |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |
Allowance for credit loss | 0 | 0 |  |  |  |  |
Asset Pledged as Collateral |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |
Investment securities pledged as collateral | $ 364,400,000 | $ 364,400,000 |  |  | $ 429,900,000 |  |

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- Definition Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2A -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479130/326-30-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-3A Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-3B + Details
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