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Loans and Allowance for Loan Losses - Troubled Debt Restructuring by Class (Details) | Sep. 30, 2020 USD ($) loan | Dec. 31, 2019 USD ($)
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | $ 12,625,000 | $ 11,333,000
Troubled debt restructuring, loans acquired, number of loans | loan | 1 |
Troubled debt restructuring, loans acquired | $ 276,000 | 0
Financing receivable, modifications, recorded investment, nonaccrual status | 300,000 | 58,000
Commercial loans | Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | 1,017,000 | 1,223,000
Commercial real estate loans | Commercial real estate, owner-occupied |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | 7,003,000 | 6,998,000
Commercial real estate loans | Commercial real estate, investor-owned |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | 3,309,000 | 1,770,000
Residential loans | Home equity |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | 527,000 | 251,000
Residential loans | Other residential |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | 0 | 452,000
Consumer loans | Installment and other consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in troubled debt restructurings | $ 769,000 | $ 639,000

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