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Loans and Loans Held for Sale - Restructured Loans by Type of Concession (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 USD ($) loan | Dec. 31, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 36 | 53
Pre-Modification Outstanding Recorded Investment | [1] | $ 5,757 | $ 14,074
Post-Modification Outstanding Recorded Investment | [1] | 6,142 | 12,192
Total Difference in Recorded Investment |  | $ 385 | $ (1,882)
Chapter 7 bankruptcy |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan | [2] | 26 | 29
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 770 | $ 1,840
Post-Modification Outstanding Recorded Investment | [1],[2] | 709 | 1,712
Total Difference in Recorded Investment | [2] | $ (61) | $ (128)
Interest rate reduction |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 0 | 1
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 250
Post-Modification Outstanding Recorded Investment | [1] | 0 | 242
Total Difference in Recorded Investment |  | $ 0 | $ (8)
Maturity date extension |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 3 | 13
Pre-Modification Outstanding Recorded Investment | [1] | $ 905 | $ 6,795
Post-Modification Outstanding Recorded Investment | [1] | 1,406 | 5,197
Total Difference in Recorded Investment |  | $ 501 | $ (1,598)
Maturity date extension and interest rate reduction |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 3 | 3
Pre-Modification Outstanding Recorded Investment | [1] | $ 1,973 | $ 884
Post-Modification Outstanding Recorded Investment | [1] | 1,918 | 877
Total Difference in Recorded Investment |  | $ (55) | $ (7)
Principal deferral |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 2 | 7
Pre-Modification Outstanding Recorded Investment | [1] | $ 113 | $ 4,305
Post-Modification Outstanding Recorded Investment | [1] | 113 | 4,164
Total Difference in Recorded Investment |  | $ 0 | $ (141)
Principal forgiveness |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 2 | 0
Pre-Modification Outstanding Recorded Investment | [1] | $ 1,996 | $ 0
Post-Modification Outstanding Recorded Investment | [1] | 1,996 | 0
Total Difference in Recorded Investment |  | $ 0 | $ 0
Commercial real estate | Chapter 7 bankruptcy |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan | [2] | 0 | 1
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 0 | $ 709
Post-Modification Outstanding Recorded Investment | [1],[2] | 0 | 646
Total Difference in Recorded Investment | [2] | $ 0 | $ (63)
Commercial real estate | Interest rate reduction |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 0 | 1
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 250
Post-Modification Outstanding Recorded Investment | [1] | 0 | 242
Total Difference in Recorded Investment |  | $ 0 | $ (8)
Commercial real estate | Maturity date extension |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 1 | 0
Pre-Modification Outstanding Recorded Investment | [1] | $ 400 | $ 0
Post-Modification Outstanding Recorded Investment | [1] | 398 | 0
Total Difference in Recorded Investment |  | $ (2) | $ 0
Commercial and industrial | Maturity date extension |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 1 | 4
Pre-Modification Outstanding Recorded Investment | [1] | $ 274 | $ 4,756
Post-Modification Outstanding Recorded Investment | [1] | 777 | 3,334
Total Difference in Recorded Investment |  | $ 503 | $ (1,422)
Commercial and industrial | Maturity date extension and interest rate reduction |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 2 | 0
Pre-Modification Outstanding Recorded Investment | [1] | $ 1,800 | $ 0
Post-Modification Outstanding Recorded Investment | [1] | 1,805 | 0
Total Difference in Recorded Investment |  | $ 5 | $ 0
Commercial and industrial | Principal deferral |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 2 | 5
Pre-Modification Outstanding Recorded Investment | [1] | $ 113 | $ 985
Post-Modification Outstanding Recorded Investment | [1] | 113 | 986
Total Difference in Recorded Investment |  | $ 0 | $ 1
Commercial construction | Maturity date extension |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 0 | 3
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 1,251
Post-Modification Outstanding Recorded Investment | [1] | 0 | 1,151
Total Difference in Recorded Investment |  | $ 0 | $ (100)
Commercial construction | Principal forgiveness |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 2 | 0
Pre-Modification Outstanding Recorded Investment | [1] | $ 1,996 | $ 0
Post-Modification Outstanding Recorded Investment | [1] | 1,996 | 0
Total Difference in Recorded Investment |  | $ 0 | $ 0
Residential mortgage | Chapter 7 bankruptcy |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan | [2] | 1 | 7
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 33 | $ 439
Post-Modification Outstanding Recorded Investment | [1],[2] | 31 | 413
Total Difference in Recorded Investment | [2] | $ (2) | $ (26)
Residential mortgage | Maturity date extension |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 0 | 1
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 483
Post-Modification Outstanding Recorded Investment | [1] | 0 | 414
Total Difference in Recorded Investment |  | $ 0 | $ (69)
Residential mortgage | Maturity date extension and interest rate reduction |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 0 | 1
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 280
Post-Modification Outstanding Recorded Investment | [1] | 0 | 279
Total Difference in Recorded Investment |  | $ 0 | $ (1)
Residential mortgage | Principal deferral |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 0 | 1
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 3,273
Post-Modification Outstanding Recorded Investment | [1] | 0 | 3,133
Total Difference in Recorded Investment |  | $ 0 | $ (140)
Home equity | Chapter 7 bankruptcy |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan | [2] | 21 | 19
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 689 | $ 676
Post-Modification Outstanding Recorded Investment | [1],[2] | 643 | 643
Total Difference in Recorded Investment | [2] | $ (46) | $ (33)
Home equity | Maturity date extension |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 1 | 5
Pre-Modification Outstanding Recorded Investment | [1] | $ 231 | $ 305
Post-Modification Outstanding Recorded Investment | [1] | 231 | 298
Total Difference in Recorded Investment |  | $ 0 | $ (7)
Home equity | Maturity date extension and interest rate reduction |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 1 | 2
Pre-Modification Outstanding Recorded Investment | [1] | $ 173 | $ 604
Post-Modification Outstanding Recorded Investment | [1] | 113 | 598
Total Difference in Recorded Investment |  | $ (60) | $ (6)
Home equity | Principal deferral |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan |  | 0 | 1
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 47
Post-Modification Outstanding Recorded Investment | [1] | 0 | 45
Total Difference in Recorded Investment |  | $ 0 | $ (2)
Installment and other consumer | Chapter 7 bankruptcy |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Loans | loan | [2] | 4 | 2
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 48 | $ 16
Post-Modification Outstanding Recorded Investment | [1],[2] | 35 | 10
Total Difference in Recorded Investment | [2] | $ (13) | $ (6)
[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
[2] | Chapter 7 bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed.

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