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Loans and Loans Held for Sale - Restructured Loans During Periods Presented (Detail) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2016 USD ($) contract | Jun. 30, 2015 USD ($) contract | Jun. 30, 2016 USD ($) contract | Jun. 30, 2015 USD ($) contract
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 22 | 7 |  | 38 |  | 27 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 10,707 | $ 796 |  | $ 13,353 |  | $ 5,408 |
Post-Modification Outstanding Recorded Investment | [1] | 8,193 | 796 |  | 10,771 |  | 5,381 |
Total Difference in Recorded Investment |  | $ (2,514) | $ 0 |  | $ (2,582) |  | $ (27) |
Principal forgiveness |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 0 | 1 |  | 0 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 400 |  | $ 0 |  | $ 400 |
Post-Modification Outstanding Recorded Investment | [1] | $ 0 | 400 |  | 0 |  | 400 |
Total Difference in Recorded Investment |  |  | $ 0 |  | $ 0 |  | $ 0 |
Principal forgiveness | Commercial and Industrial |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 0 | 1 |  | 0 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 400 |  | $ 0 |  | $ 400 |
Post-Modification Outstanding Recorded Investment | [1] | 0 | 400 |  | $ 0 |  | $ 400 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  |  |  |  |
Principal deferral |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 7 | 0 |  | 8 |  | 9 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 8,979 | $ 0 |  | $ 9,026 |  | $ 3,616 |
Post-Modification Outstanding Recorded Investment | [1] | 6,528 | 0 |  | 6,574 |  | 3,615 |
Total Difference in Recorded Investment |  | $ (2,451) | $ 0 |  | $ (2,452) |  | $ (1) |
Principal deferral | Commercial and Industrial |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 5 | 0 |  | 5 |  | 6 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 985 | $ 0 |  | $ 985 |  | $ 661 |
Post-Modification Outstanding Recorded Investment | [1] | 985 | 0 |  | $ 985 |  | $ 661 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  |  |  |  |
Principal deferral | Commercial Real Estate |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 1 | 0 |  | 1 |  | 2 |
Pre-Modification Outstanding Recorded Investment |  | $ 4,721 | $ 0 |  | $ 4,721 | [1] | $ 2,851 | [1]
Post-Modification Outstanding Recorded Investment |  | 2,270 | 0 |  | 2,270 | [1] | 2,851 | [1]
Total Difference in Recorded Investment |  | $ (2,451) | $ 0 |  | $ (2,451) |  | $ 0 |
Principal deferral | Commercial Construction |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  |  |  |  | 0 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] |  |  |  | $ 0 |  | $ 104 |
Post-Modification Outstanding Recorded Investment | [1] |  |  |  | 0 |  | 103 |
Total Difference in Recorded Investment |  |  |  |  | $ 0 |  | $ (1) |
Principal deferral | Residential Mortgage |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 1 | 0 |  | 1 |  | 0 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 3,273 | $ 0 |  | $ 3,273 |  | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] | 3,273 | 0 |  | 3,273 |  | 0 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  | $ 0 |  | $ 0 |
Principal deferral | Home Equity |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  |  |  |  | 1 |  | 0 |
Pre-Modification Outstanding Recorded Investment | [1] |  |  |  | $ 47 |  | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] |  |  |  | 46 |  | 0 |
Total Difference in Recorded Investment |  |  |  |  | $ (1) |  | $ 0 |
Chapter 7 bankruptcy |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract | [2] | 7 | 4 |  | 16 |  | 13 |
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 154 | $ 171 |  | $ 1,328 |  | $ 316 |
Post-Modification Outstanding Recorded Investment | [1],[2] | 146 | 171 |  | 1,283 |  | 305 |
Total Difference in Recorded Investment | [2] | $ (8) | $ 0 |  | $ (45) |  | $ (11) |
Chapter 7 bankruptcy | Commercial and Industrial |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract | [2] |  |  |  | 0 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1],[2] |  |  |  | $ 0 |  | $ 3 |
Post-Modification Outstanding Recorded Investment | [1],[2] |  |  |  | 0 |  | 1 |
Total Difference in Recorded Investment | [2] |  |  |  | $ 0 |  | $ (2) |
Chapter 7 bankruptcy | Commercial Real Estate |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract | [2] |  |  |  | 1 |  | 0 |
Pre-Modification Outstanding Recorded Investment | [1],[2] |  |  |  | $ 709 |  | $ 0 |
Post-Modification Outstanding Recorded Investment | [1],[2] |  |  |  | 681 |  | 0 |
Total Difference in Recorded Investment | [2] |  |  |  | $ (28) |  | $ 0 |
Chapter 7 bankruptcy | Residential Mortgage |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract | [2] | 1 | 0 |  | 4 |  |  |
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 65 | $ 0 |  | $ 285 |  |  |
Post-Modification Outstanding Recorded Investment | [1],[2] | 64 | 0 |  | 280 |  |  |
Total Difference in Recorded Investment | [2] | $ (1) | $ 0 |  | $ (5) |  |  |
Chapter 7 bankruptcy | Home Equity |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract | [2] | 4 | 4 |  | 9 |  | 12 |
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 73 | $ 171 |  | $ 318 |  | $ 313 |
Post-Modification Outstanding Recorded Investment | [1],[2] | 69 | 171 |  | 309 |  | 304 |
Total Difference in Recorded Investment | [2] | $ (4) | $ 0 |  | $ (9) |  | $ (9) |
Chapter 7 bankruptcy | Installment and Other Consumer |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract | [2] | 2 | 0 |  | 2 |  |  |
Pre-Modification Outstanding Recorded Investment | [1],[2] | $ 16 | $ 0 |  | $ 16 |  |  |
Post-Modification Outstanding Recorded Investment | [1],[2] | 13 | 0 |  | 13 |  |  |
Total Difference in Recorded Investment | [2] | $ (3) | $ 0 |  | $ (3) |  |  |
Interest rate reduction |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 0 | 0 |  | 0 |  |  |
Pre-Modification Outstanding Recorded Investment | [1] |  |  |  | $ 0 |  |  |
Post-Modification Outstanding Recorded Investment | [1] |  | $ 0 |  | 0 |  |  |
Total Difference in Recorded Investment |  |  | $ 0 |  | $ 0 |  |  |
Maturity date extension and interest rate reduction |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 0 | 2 |  | 1 |  | 2 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 0 | $ 225 |  | $ 130 |  | $ 225 |
Post-Modification Outstanding Recorded Investment | [1] | 0 | 225 |  | 128 |  | $ 225 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  | $ (2) |  |  |
Maturity date extension and interest rate reduction | Residential Mortgage |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 0 | 2 |  | 0 |  | 2 |
Pre-Modification Outstanding Recorded Investment |  | $ 0 | $ 225 | [1] | $ 0 | [1] | $ 225 | [1]
Post-Modification Outstanding Recorded Investment |  | 0 | 225 | [1] | $ 0 | [1] | $ 225 | [1]
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  |  |  |  |
Maturity date extension and interest rate reduction | Home Equity |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  |  |  |  | 1 |  | 0 |
Pre-Modification Outstanding Recorded Investment | [1] |  |  |  | $ 130 |  | $ 0 |
Post-Modification Outstanding Recorded Investment | [1] |  |  |  | 128 |  | 0 |
Total Difference in Recorded Investment |  |  |  |  | $ (2) |  | $ 0 |
Maturity date extension |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 8 | 0 |  | 13 |  | 2 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 1,574 | $ 0 |  | $ 2,869 |  | $ 851 |
Post-Modification Outstanding Recorded Investment | [1] | 1,519 | 0 |  | 2,786 |  | 836 |
Total Difference in Recorded Investment |  | $ (55) | $ 0 |  | $ (83) |  | $ (15) |
Maturity date extension | Commercial and Industrial |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 1 | 0 |  | 3 |  | 1 |
Pre-Modification Outstanding Recorded Investment | [1] | $ 130 | $ 0 |  | $ 755 |  | $ 780 |
Post-Modification Outstanding Recorded Investment | [1] | 130 | 0 |  | 728 |  | 765 |
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  | $ (27) |  | $ (15) |
Maturity date extension | Commercial Construction |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 4 | 0 |  | 5 |  | 0 |
Pre-Modification Outstanding Recorded Investment |  | $ 1,324 | $ 0 |  | $ 1,357 | [1] |  |
Post-Modification Outstanding Recorded Investment |  | 1,269 | 0 |  | 1,303 | [1] |  |
Total Difference in Recorded Investment |  | $ (55) | $ 0 |  | $ (54) |  |  |
Maturity date extension | Residential Mortgage |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  |  |  |  | 1 |  |  |
Pre-Modification Outstanding Recorded Investment | [1] |  |  |  | $ 483 |  |  |
Post-Modification Outstanding Recorded Investment | [1] |  |  |  | $ 483 |  |  |
Maturity date extension | Home Equity |  |  |  |  |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |  |  |  |  |
Number of Loans | contract |  | 3 | 0 |  | 4 |  | 1 |
Pre-Modification Outstanding Recorded Investment |  | $ 120 | $ 0 |  | $ 274 | [1] | $ 71 | [1]
Post-Modification Outstanding Recorded Investment |  | 120 | 0 |  | 272 | [1] | $ 71 | [1]
Total Difference in Recorded Investment |  | $ 0 | $ 0 |  | $ (2) |  |  |
[1] | (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] | (2) Chapter 7 bankruptcy loans where the debt has been legally discharged through the bankruptcy court and not reaffirmed.

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