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Investment Securities - Schedule of Allowance for Credit Losses HTM (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Held-to-maturity |  |  |  |
Beginning balance | $ 3,214 | $ 3,214 | $ 3,214 | $ 3,214
Provision for credit loss expense | 0 | 0 | 0 | 0
Net increase (decrease) in allowance on previously impaired securities | 0 | 0 | 0 | 0
Ending balance | 3,214 | 3,214 | 3,214 | 3,214
State and political subdivisions |  |  |  |
Held-to-maturity |  |  |  |
Beginning balance | 171 | 2,252 | 196 | 2,006
Provision for credit loss expense | 0 | 0 | 0 | 0
Net increase (decrease) in allowance on previously impaired securities | 31 | (2,061) | 6 | (1,815)
Ending balance | 202 | 191 | 202 | 191
Other securities |  |  |  |
Held-to-maturity |  |  |  |
Beginning balance | 3,043 | 962 | 3,018 | 1,208
Provision for credit loss expense | 0 | 0 | 0 | 0
Net increase (decrease) in allowance on previously impaired securities | (31) | 2,061 | (6) | 1,815
Ending balance | $ 3,012 | $ 3,023 | $ 3,012 | $ 3,023

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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 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-22 + 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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