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Investment Securities - Allowance for Credit Losses HTM (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Held-to-maturity |  |
Beginning balance | $ 1,388 | $ 1,279
Provision for credit loss expense | 500 | 0
Recoveries |  | 98
Ending balance | 1,888 | 1,377
State and political subdivisions |  |
Held-to-maturity |  |
Beginning balance | 110 | 1,197
Provision for credit loss expense | 252 | 0
Recoveries |  | 88
Ending balance | 362 | 1,285
Other securities |  |
Held-to-maturity |  |
Beginning balance | 1,278 | 82
Provision for credit loss expense | 248 | 0
Recoveries |  | 10
Ending balance | $ 1,526 | $ 92

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 + Details
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- Definition Amount of increase in allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity), from recovery. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 + 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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