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Securities - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Securities available-for-sale, at fair value, post ASU 2019-04 | $ 501,336,000 |  | $ 501,336,000 |  | $ 408,410,000
Gross gains | 0 |  | 0 |  |
Realized losses |  | $ 6,800,000 |  | $ 6,800,000 |
Provision for credit losses, HTM | 0 | 0 | 0 | 0 |
Provision for credit losses, AFS | 0 | $ 0 | 0 | $ 0 |
Impairment on other investments |  |  | 0 |  |
Securities held-to-maturity, at amortized cost, post ASU 2019-04 | 127,779,000 |  | 127,779,000 |  | 281,236,000
Allowance for off balance sheet credit | 2,300,000 |  | 2,300,000 |  | 2,400,000
Asset Pledged as Collateral [Member] | Secure Public Funds and Securities Sold under Agreements to Repurchase [Member] |  |  |  |  |
Securities available-for-sale, at fair value, post ASU 2019-04 | $ 452,500,000 |  | $ 452,500,000 |  | $ 358,300,000

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- Definition Amount excluding accrued interest, of 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/2009/role/commonPracticeRef -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 + Details
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- Definition Amount of realized gain 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 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-9 + Details
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- Definition Amount of realized loss 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 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-9 + Details
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- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482454/460-10-45-1 + Details
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