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Investment Securities - Allowance for Credit Losses HTM (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Beginning balance | $ 1,279 | $ 2,915
Provision for credit loss expense | 0 | (697)
Securities charged-off | 0 | 600
Recoveries | 98 |
Ending balance | 1,377 | 1,618
State and political subdivisions |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Beginning balance | 1,197 | 2,307
Provision for credit loss expense | 0 | (1,265)
Securities charged-off | 0 | 0
Recoveries | 88 |
Ending balance | 1,285 | 1,042
Other securities |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Beginning balance | 82 | 608
Provision for credit loss expense | 0 | 568
Securities charged-off | 0 | 600
Recoveries | 10 |
Ending balance | $ 92 | $ 576

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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 http://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 http://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 http://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 http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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