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Loans and Loans Held for Sale - Summary of Restructured Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016 | Dec. 31, 2016
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans | [1] | $ 2,665 | $ 8,193 | $ 3,103 | $ 10,771 |
Performing TDRs |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 15,080 |  | $ 13,423
Performing TDRs | Commercial Real Estate |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 2,672 |  | 2,994
Performing TDRs | Commercial and Industrial |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 3,324 |  | 1,387
Performing TDRs | Commercial Construction |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 2,953 |  | 2,966
Performing TDRs | Residential Mortgage |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 2,235 |  | 2,375
Performing TDRs | Home Equity Loan |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 3,866 |  | 3,683
Performing TDRs | Installment And Other Consumer |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 30 |  | 18
Nonperforming TDRs |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 10,105 |  | 11,598
Nonperforming TDRs | Commercial Real Estate |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 704 |  | 646
Nonperforming TDRs | Commercial and Industrial |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 3,944 |  | 4,493
Nonperforming TDRs | Commercial Construction |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 423 |  | 430
Nonperforming TDRs | Residential Mortgage |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 4,111 |  | 5,068
Nonperforming TDRs | Home Equity Loan |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 918 |  | 954
Nonperforming TDRs | Installment And Other Consumer |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 5 |  | 7
Total TDRs |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 25,185 |  | 25,021
Total TDRs | Commercial Real Estate |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 3,376 |  | 3,640
Total TDRs | Commercial and Industrial |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 7,268 |  | 5,880
Total TDRs | Commercial Construction |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 3,376 |  | 3,396
Total TDRs | Residential Mortgage |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 6,346 |  | 7,443
Total TDRs | Home Equity Loan |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | 4,784 |  | 4,637
Total TDRs | Installment And Other Consumer |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |
Restructured loans |  |  |  | $ 35 |  | $ 25
[1] | Excludes loans that were fully paid off or fully charged-off by period end. The pre-modification balance represents the balance outstanding prior to modification. The post-modification balance represents the outstanding balance at period end.

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