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Investment Securities - Allowance for Credit Losses HTM (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |  |  |
Beginning balance | $ 1,381 | $ 1,132 | $ 1,279 | $ 2,915
Provision for credit loss expense | 0 | 0 | 0 | (1,183)
Net increase (decrease) in allowance on previously impaired securities | 0 |  | 0 | (600)
Recoveries | 3 | 147 | 105 | 147
Ending balance | 1,384 | 1,279 | 1,384 | 1,279
State and political subdivisions |  |  |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |  |  |
Beginning balance | 103 | 871 | 1,197 | 2,307
Provision for credit loss expense | 0 | 325 | 0 | (1,111)
Net increase (decrease) in allowance on previously impaired securities | 3 |  | (1,180) | 0
Recoveries | 1 | 0 | 90 | 0
Ending balance | 107 | 1,196 | 107 | 1,196
Other securities |  |  |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |  |  |
Beginning balance | 1,278 | 261 | 82 | 608
Provision for credit loss expense | 0 | (325) | 0 | (72)
Net increase (decrease) in allowance on previously impaired securities | (3) |  | 1,180 | (600)
Recoveries | 2 | 147 | 15 | 147
Ending balance | $ 1,277 | $ 83 | $ 1,277 | $ 83

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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 writeoff of investment in debt security, measured at amortized cost (held-to-maturity), charged against allowance for credit loss. + 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 (d) -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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