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Loans and Allowance for Credit Losses - Troubled Debt Restructuring by Class (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in troubled debt restructurings	$ 10,775	$ 12,506
Financing receivable, modifications, recorded investment, nonaccrual status	7,400	7,400
Unfunded commitments for TDR loans	845
Commercial loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in troubled debt restructurings	854	1,021
Commercial real estate loans | Commercial owner-occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in troubled debt restructurings	7,147	7,147
Commercial real estate loans | Commercial investor-owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in troubled debt restructurings	1,741	3,305
Residential loans | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in troubled debt restructurings	277	281
Consumer loans | Installment and other consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in troubled debt restructurings	$ 756	$ 752

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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