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Loans and Allowance for Credit Losses on Loans - Troubled Debt Restructuring by Class (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | $ 11,246 | $ 12,506
Financing receivable, modifications, recorded investment, nonaccrual status | 7,400 | 7,400
Unfunded commitments for TDR loans | 242 |
Commercial loans | Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | 1,394 | 1,021
Unfunded commitments for TDR loans | 600 |
Commercial real estate loans | Commercial owner-occupied |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | 7,155 | 7,147
Commercial real estate loans | Commercial investor-owned |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | 1,718 | 3,305
Residential loans | Home equity |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | 273 | 281
Consumer loans | Installment and other consumer loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | $ 706 | $ 752

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