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Investment Securities - Allowance for Credit Losses HTM (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Held-to-maturity |  |
Beginning balance | $ 3,214 | $ 1,388
Provision for credit loss expense | 0 | 500
Net increase (decrease) in allowance on previously impaired securities | 0 |
Ending balance | 3,214 | 1,888
State and political subdivisions |  |
Held-to-maturity |  |
Beginning balance | 2,006 | 110
Provision for credit loss expense | 0 | 252
Net increase (decrease) in allowance on previously impaired securities | 246 |
Ending balance | 2,252 | 362
Other securities |  |
Held-to-maturity |  |
Beginning balance | 1,208 | 1,278
Provision for credit loss expense | 0 | 248
Net increase (decrease) in allowance on previously impaired securities | (246) |
Ending balance | $ 962 | $ 1,526

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- Definition Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479344/326-20-45-1 + Details
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- Definition Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 + Details
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- Definition Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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