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Loans and Allowance for Credit Losses - Troubled Debt Restructuring Modifications (Details) $ in Thousands | 3 Months Ended
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Mar. 31, 2021 USD ($) loan contract | Mar. 31, 2020 USD ($) loan contract
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Number of Contracts Modified | contract | 0 | 3
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 273
Post-Modification Outstanding Recorded Investment | 0 | 265
Post-Modification Outstanding Recorded Investment at Period End | $ 0 | $ 247
Number of modified TDR loans that defaulted | loan | 0 | 0
Commercial and industrial | Commercial loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Number of Contracts Modified | contract |  | 1
Pre-Modification Outstanding Recorded Investment |  | $ 170
Post-Modification Outstanding Recorded Investment |  | 162
Post-Modification Outstanding Recorded Investment at Period End |  | $ 144
Installment and other consumer loans | Consumer loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Number of Contracts Modified | contract |  | 2
Pre-Modification Outstanding Recorded Investment |  | $ 103
Post-Modification Outstanding Recorded Investment |  | 103
Post-Modification Outstanding Recorded Investment at Period End |  | $ 103

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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
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- Definition Amount, after troubled debt restructuring, of modified financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
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- Definition Amount, before troubled debt restructuring, of financing receivable to be modified. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
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- Definition Amount of increase (decrease) in financing receivable modified from troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
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