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Loans and Loans Held for Sale - Restructured Loans By Segment and Type of Concession (Details) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 USD ($) loan | Mar. 31, 2017 USD ($) loan
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  | 21 | 7 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 6,876 | $ 442 |
Post-Modification Outstanding Recorded Investment | [1] | 6,770 | 438 |
Total Difference in Recorded Investment |  | $ (106) | $ (4) |
Maturity date extension |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  | 2 | 0 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 768 | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] | 708 | 0 |
Total Difference in Recorded Investment |  | $ (60) | $ 0 |
Principal deferral |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  | 6 | 0 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 5,355 | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] | 5,333 | 0 |
Total Difference in Recorded Investment |  | $ (22) | $ 0 |
Chapter 7 bankruptcy |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | [2] | 13 | 6 |
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 753 | $ 269 |
Post-Modification Outstanding Recorded Investment | [1],[2] | 729 | 266 |
Total Difference in Recorded Investment | [2] | $ (24) | $ (3) |
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 | $ 173 |
Post-Modification Outstanding Recorded Investment | [1] | 0 | 172 |
Total Difference in Recorded Investment |  | $ 0 | $ (1) |
Commercial and industrial |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  | 8 | 0 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 6,123 | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] | 6,041 | 0 |
Total Difference in Recorded Investment |  | $ (82) | $ 0 |
Commercial and industrial | Maturity date extension |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  | 2 | 0 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 768 | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] | 708 | 0 |
Total Difference in Recorded Investment |  | $ (60) | $ 0 |
Commercial and industrial | Principal deferral |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  | 6 | 0 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 5,355 | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] | 5,333 | 0 |
Total Difference in Recorded Investment |  | $ (22) | $ 0 |
Commercial construction |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  | 2 | 0 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 158 | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] | 157 | 0 |
Total Difference in Recorded Investment |  | $ (1) | $ 0 |
Commercial construction | Chapter 7 bankruptcy |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | [2] | 2 | 0 |
Pre-Modification Outstanding Recorded Investment | [2] | $ 158 | $ 0 |
Post-Modification Outstanding Recorded Investment | [2] | 157 | 0 | [1]
Total Difference in Recorded Investment | [2] | $ (1) | $ 0 |
Home equity |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  | 9 | 7 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 578 | $ 442 |
Post-Modification Outstanding Recorded Investment | [1] | 555 | 438 |
Total Difference in Recorded Investment |  | $ (23) | $ (4) |
Home equity | Chapter 7 bankruptcy |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | [2] | 9 | 6 |
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 578 | $ 269 |
Post-Modification Outstanding Recorded Investment | [1],[2] | 555 | 266 |
Total Difference in Recorded Investment | [2] | $ (23) | $ (3) |
Home equity | 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 | $ 173 |
Post-Modification Outstanding Recorded Investment | [1] | 0 | 172 |
Total Difference in Recorded Investment |  | $ 0 | $ (1) |
Installment and other consumer |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan |  | 2 | 0 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 17 | $ 0 |
Post-Modification Outstanding Recorded Investment |  | 17 | 0 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |
Installment and other consumer | Chapter 7 bankruptcy |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of Loans | loan | [2] | 2 | 0 |
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 17 | $ 0 |
Post-Modification Outstanding Recorded Investment | [2] | 17 | 0 |
Total Difference in Recorded Investment | [2] | $ 0 | $ 0 |
[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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