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Loans and Allowance for Loan Losses - Troubled Debt Restructuring by Class (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2017 USD ($) loans | Dec. 31, 2016 USD ($) loans
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Number of loans removed from TDR designation | loans | 0 | 0
Recorded investment in Troubled Debt Restructurings | $ 17,240,000 | $ 18,168,000
Accruing TDR loans | 0 | 0
TDR loans acquired |  | 0
Commercial loans | Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in Troubled Debt Restructurings | 2,070,000 | 2,207,000
Commercial real estate loans | Commercial real estate, owner-occupied |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in Troubled Debt Restructurings | 7,001,000 | 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 | 2,235,000 | 2,256,000
Commercial real estate loans | Construction |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in Troubled Debt Restructurings | 3,241,000 | 3,245,000
Residential loans | Home equity |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in Troubled Debt Restructurings | 623,000 | 625,000
Residential loans | Other residential |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in Troubled Debt Restructurings | 1,175,000 | 1,965,000
Consumer loans | Installment and other consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Recorded investment in Troubled Debt Restructurings | $ 895,000 | $ 877,000

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