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Loans and Loans Held for Sale - Restructured Loans During Periods Presented (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 USD ($) contract | Jun. 30, 2016 USD ($) contract | Jun. 30, 2017 USD ($) contract | Jun. 30, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 11 | 22 |  | 18 |  | 38 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 2,670 | $ 10,707 |  | $ 3,112 |  | $ 13,353 |
Post-Modification Outstanding Recorded Investment | [1] | 2,665 | 8,193 |  | 3,103 |  | 10,771 |
Total Difference in Recorded Investment |  | $ (5) | $ (2,514) |  | $ (9) |  | $ (2,582) |
Principal deferral |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 2 | 7 |  | 2 |  | 8 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 529 | $ 8,979 |  | $ 529 |  | $ 9,026 |
Post-Modification Outstanding Recorded Investment | [1] | 529 | 6,528 |  | 529 |  | 6,574 |
Total Difference in Recorded Investment |  | $ 0 | $ (2,451) |  | $ 0 |  | $ (2,452) |
Chapter 7 bankruptcy |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 6 | 7 | [2] | 12 | [2] | 16 | [2]
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 110 | $ 154 |  | $ 379 |  | $ 1,328 |
Post-Modification Outstanding Recorded Investment | [1],[2] | 105 | 146 |  | 371 |  | 1,283 |
Total Difference in Recorded Investment | [2] | $ (5) | $ (8) |  | $ (8) |  | $ (45) |
Maturity date extension and interest rate reduction |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 2 | 0 |  | 3 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 1,800 | $ 0 |  | $ 1,973 |  | $ 130 |
Post-Modification Outstanding Recorded Investment | [1] | 1,800 | 0 |  | 1,972 |  | 128 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  | $ (1) |  | $ (2) |
Maturity date extension |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 1 | 8 |  | 1 |  | 13 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 231 | $ 1,574 |  | $ 231 |  | $ 2,869 |
Post-Modification Outstanding Recorded Investment | [1] | 231 | 1,519 |  | 231 |  | 2,786 |
Total Difference in Recorded Investment |  | $ 0 | $ (55) |  | $ 0 |  | $ (83) |
Commercial Real Estate | Principal deferral |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 1 | 1 |  | 1 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 100 | $ 4,721 |  | $ 100 |  | $ 4,721 |
Post-Modification Outstanding Recorded Investment | [1] | 100 | 2,270 |  | $ 100 |  | 2,270 |
Total Difference in Recorded Investment |  | $ 0 | $ (2,451) |  |  |  | $ (2,451) |
Commercial Real Estate | Chapter 7 bankruptcy |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract | [2] |  |  |  | 0 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1],[2] |  |  |  | $ 0 |  | $ 709 |
Post-Modification Outstanding Recorded Investment | [1],[2] |  |  |  | $ 0 |  | 681 |
Total Difference in Recorded Investment | [2] |  |  |  |  |  | $ (28) |
Commercial and Industrial | Principal deferral |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 1 | 5 |  | 1 |  | 5 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 429 | $ 985 |  | $ 429 |  | $ 985 |
Post-Modification Outstanding Recorded Investment | [1] | 429 | 985 |  | 429 |  | $ 985 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  | $ 0 |  |  |
Commercial and Industrial | Maturity date extension and interest rate reduction |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 2 | 0 |  | 2 |  | 0 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 1,800 | $ 0 |  | $ 1,800 |  | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] | 1,800 | 0 |  | 1,800 |  | $ 0 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  | $ 0 |  |  |
Commercial and Industrial | Maturity date extension |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 0 | 1 |  | 0 |  | 3 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 130 |  | $ 0 |  | $ 755 |
Post-Modification Outstanding Recorded Investment | [1] | 0 | 130 |  | 0 |  | 728 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  | $ 0 |  | $ (27) |
Commercial Construction | Maturity date extension |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 0 | 4 |  | 0 |  | 5 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 1,324 |  | $ 0 |  | $ 1,357 |
Post-Modification Outstanding Recorded Investment | [1] | 0 | 1,269 |  | $ 0 |  | 1,303 |
Total Difference in Recorded Investment |  | $ 0 | $ (55) |  |  |  | $ (54) |
Residential Mortgage | Principal deferral |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 0 | 1 |  | 0 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 3,273 |  | $ 0 |  | $ 3,273 |
Post-Modification Outstanding Recorded Investment | [1] | 0 | 3,273 |  | 0 |  | 3,273 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  | $ 0 |  | $ 0 |
Residential Mortgage | Chapter 7 bankruptcy |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 1 | 1 | [2] | 1 | [2] | 4 | [2]
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 33 | $ 65 |  | $ 33 |  | $ 285 |
Post-Modification Outstanding Recorded Investment | [1],[2] | 33 | 64 |  | 33 |  | 280 |
Total Difference in Recorded Investment | [2] | $ 0 | $ (1) |  |  |  | $ (5) |
Residential Mortgage | Maturity date extension |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  |  |  |  |  |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] |  |  |  |  |  | $ 483 |
Post-Modification Outstanding Recorded Investment | [1] |  |  |  |  |  | 483 |
Total Difference in Recorded Investment |  |  |  |  | $ 0 |  | $ 0 |
Home Equity Loan | Principal deferral |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  |  |  |  | 0 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] |  |  |  | $ 0 |  | $ 47 |
Post-Modification Outstanding Recorded Investment | [1] |  |  |  | 0 |  | 46 |
Total Difference in Recorded Investment |  |  |  |  | $ 0 |  | $ (1) |
Home Equity Loan | Chapter 7 bankruptcy |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 3 | 4 | [2] | 9 | [2] | 9 | [2]
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 40 | $ 73 |  | $ 309 |  | $ 318 |
Post-Modification Outstanding Recorded Investment | [1],[2] | 38 | 69 |  | 304 |  | 309 |
Total Difference in Recorded Investment | [2] | $ (2) | $ (4) |  | $ (5) |  | $ (9) |
Home Equity Loan | Maturity date extension and interest rate reduction |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  |  |  |  | 1 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] |  |  |  | $ 173 |  | $ 130 |
Post-Modification Outstanding Recorded Investment | [1] |  |  |  | 172 |  | 128 |
Total Difference in Recorded Investment |  |  |  |  | $ (1) |  | $ (2) |
Home Equity Loan | Maturity date extension |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 1 | 3 |  | 1 |  | 4 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 231 | $ 120 |  | $ 231 |  | $ 274 |
Post-Modification Outstanding Recorded Investment | [1] | 231 | 120 |  | $ 231 |  | 272 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  |  |  | $ (2) |
Installment and Other Consumer | Chapter 7 bankruptcy |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 2 | 2 | [2] | 2 | [2] | 2 | [2]
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 37 | $ 16 |  | $ 37 |  | $ 16 |
Post-Modification Outstanding Recorded Investment | [1],[2] | 34 | 13 |  | 34 |  | 13 |
Total Difference in Recorded Investment | [2] | $ (3) | $ (3) |  | $ (3) |  | $ (3) |
[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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