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Investment Securities - Allowance for Credit Losses HTM (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2020
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Beginning balance | $ 307 | $ 0
Provision for credit loss expense | 66 | 4
Ending balance, September 30, 2020 | 373 | 373
State and political subdivisions |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Beginning balance | 95 | 0
Provision for credit loss expense | (22) | 15
Ending balance, September 30, 2020 | 73 | 73
Other securities |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Beginning balance | 212 | 0
Provision for credit loss expense | 88 | (11)
Ending balance, September 30, 2020 | $ 300 | 300
Impact of ASU 2016-13 adoption |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Beginning balance |  | 369
Impact of ASU 2016-13 adoption | State and political subdivisions |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Beginning balance |  | 58
Impact of ASU 2016-13 adoption | Other securities |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Beginning balance |  | $ 311

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- Definition Amount of allowance for credit loss for 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 (a) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aaa) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121599337&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=121599337&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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