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Loans and Allowance for Loan Losses - Troubled Debt Restructuring by Class (Details) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2019 USD ($) loan | Sep. 30, 2018 USD ($) loan | Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Recorded investment of loans removed from TDR resignation | $ 3,000 | $ 247,000 |
Recorded investment in Troubled Debt Restructurings | 12,162,000 |  | $ 14,406,000
TDR loans acquired | 0 |  | 0
TDR loans on non-accrual status | $ 233,000 |  | 65,000
Commercial loans |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Number of loans removed from TDR designation | loan | 1 |  |
Commercial loans | Commercial and industrial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Recorded investment in Troubled Debt Restructurings | $ 1,139,000 |  | 1,506,000
Commercial real estate loans | Commercial real estate, owner-occupied |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Recorded investment in Troubled Debt Restructurings | 6,999,000 |  | 6,993,000
Commercial real estate loans | Commercial real estate, investor |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Recorded investment in Troubled Debt Restructurings | 1,786,000 |  | 1,821,000
Commercial real estate loans | Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Recorded investment in Troubled Debt Restructurings | 880,000 |  | 2,688,000
Residential loans | Home equity |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Number of loans removed from TDR designation | loan |  | 1 |
Recorded investment in Troubled Debt Restructurings | 251,000 |  | 251,000
Residential loans | Other residential |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Number of loans removed from TDR designation | loan |  | 1 |
Recorded investment in Troubled Debt Restructurings | 454,000 |  | 462,000
Consumer loans | Installment and other consumer |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Recorded investment in Troubled Debt Restructurings | $ 653,000 |  | $ 685,000

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