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Loans and Allowance for Loan Losses - Troubled Debt Restructuring by Class (Details) | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2015 USD ($) loans | Sep. 30, 2016 USD ($) | Sep. 30, 2015 USD ($) | Sep. 30, 2016 USD ($) loans | Sep. 30, 2015 USD ($) loans | Dec. 31, 2015 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Number of loans removed from TDR designation | loans |  |  |  | 0 | 4 |
Loans removed from TDR designation, recorded investment |  |  |  |  | $ 1,400,000 |
Recorded investment in Troubled Debt Restructurings |  | $ 19,188,000 |  | $ 19,188,000 |  | $ 19,081,000
TDR loans accruing interest as of period end |  | 19,100,000 |  | 19,100,000 |  | 19,000,000
TDR loans acquired |  | 0 |  | 0 |  | 137,000
Number of loans transferred to loans held-for-sale | loans | 1 |  |  |  |  |
Charge-off on loan transferred to held-for-sale |  | 0 | $ 3,000 | 13,000 | 856,000 |
Gain (loss) on transfer of loans to held-for-sale | $ 0 |  |  |  |  |
Commercial loans | Commercial and industrial |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Recorded investment in Troubled Debt Restructurings |  | 2,964,000 |  | 2,964,000 |  | 4,698,000
Charge-off on loan transferred to held-for-sale |  | 0 | 2,000 | 9,000 | 5,000 |
Commercial real estate loans | Commercial real estate, owner-occupied |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Recorded investment in Troubled Debt Restructurings |  | 6,993,000 |  | 6,993,000 |  | 6,993,000
Charge-off on loan transferred to held-for-sale |  | 0 | 0 | 0 | 0 |
Commercial real estate loans | Commercial real estate, investor |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Recorded investment in Troubled Debt Restructurings |  | 2,299,000 |  | 2,299,000 |  | 514,000
Charge-off on loan transferred to held-for-sale |  | 0 | 0 | 0 | 0 |
Commercial real estate loans | Construction |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Recorded investment in Troubled Debt Restructurings |  | 3,238,000 |  | 3,238,000 |  | 3,238,000
Loans reclassified to held-for-sale | 1,500,000 |  |  |  |  |
Charge-off on loan transferred to held-for-sale | $ 839,000 | 0 | 0 | 0 | 839,000 |
Residential loans | Home equity |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Recorded investment in Troubled Debt Restructurings |  | 696,000 |  | 696,000 |  | 460,000
Charge-off on loan transferred to held-for-sale |  | 0 | 0 | 0 | 0 |
Residential loans | Other residential |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Recorded investment in Troubled Debt Restructurings |  | 1,974,000 |  | 1,974,000 |  | 2,010,000
Charge-off on loan transferred to held-for-sale |  | 0 | 0 | 0 | 0 |
Consumer loans | Installment and other consumer |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Recorded investment in Troubled Debt Restructurings |  | 1,024,000 |  | 1,024,000 |  | $ 1,168,000
Charge-off on loan transferred to held-for-sale |  | $ 0 | $ 1,000 | $ 4,000 | $ 12,000 |

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