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Loans and Loans Held for Sale - Restructured Loans for Periods Stated (Detail) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2016 USD ($) contract | Mar. 31, 2015 USD ($) contract
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 16 | 20
Pre-Modification Outstanding Recorded Investment | $ 2,646 | $ 4,612
Post-Modification Outstanding Recorded Investment | 2,614 | 4,585
Total Difference in Recorded Investment | $ (32) | $ (27)
Principal deferral |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 0 | 9
Pre-Modification Outstanding Recorded Investment |  | $ 3,616
Post-Modification Outstanding Recorded Investment | $ 0 | 3,615
Total Difference in Recorded Investment | $ 0 | $ (1)
Principal deferral | Commercial Real Estate |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 0 | 2
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 2,851
Post-Modification Outstanding Recorded Investment | 0 | 2,851
Total Difference in Recorded Investment | $ 0 | $ 0
Principal deferral | Commercial and Industrial |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 0 | 6
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 661
Post-Modification Outstanding Recorded Investment | 0 | 661
Total Difference in Recorded Investment | $ 0 | $ 0
Principal deferral | Commercial Construction |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 0 | 1
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 104
Post-Modification Outstanding Recorded Investment | 0 | 103
Total Difference in Recorded Investment | $ 0 | $ (1)
Principal deferral | Home Equity |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 0 | 0
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0
Post-Modification Outstanding Recorded Investment | 0 | 0
Total Difference in Recorded Investment | $ 0 | $ 0
Chapter 7 Bankruptcy |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 9 | 9
Pre-Modification Outstanding Recorded Investment | $ 1,175 | $ 145
Post-Modification Outstanding Recorded Investment | 1,164 | 134
Total Difference in Recorded Investment | $ (11) | $ (11)
Chapter 7 Bankruptcy | Commercial Real Estate |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 1 | 0
Pre-Modification Outstanding Recorded Investment | $ 709 | $ 0
Post-Modification Outstanding Recorded Investment | 702 | 0
Total Difference in Recorded Investment | $ (7) | $ 0
Chapter 7 Bankruptcy | Commercial and Industrial |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 0 | 1
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 3
Post-Modification Outstanding Recorded Investment | 0 | 1
Total Difference in Recorded Investment | $ 0 | $ (2)
Chapter 7 Bankruptcy | Residential Mortgage |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 3 | 0
Pre-Modification Outstanding Recorded Investment | $ 221 | $ 0
Post-Modification Outstanding Recorded Investment | 219 | 0
Total Difference in Recorded Investment | $ (2) | $ 0
Chapter 7 Bankruptcy | Home Equity |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 5 | 8
Pre-Modification Outstanding Recorded Investment | $ 245 | $ 142
Post-Modification Outstanding Recorded Investment | 243 | 133
Total Difference in Recorded Investment | $ (2) | $ (9)
Maturity date extension and interest rate reduction |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 1 | 0
Pre-Modification Outstanding Recorded Investment | $ 130 | $ 0
Post-Modification Outstanding Recorded Investment | 130 | 0
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 | $ 130 | $ 0
Post-Modification Outstanding Recorded Investment | 130 | 0
Total Difference in Recorded Investment | $ 0 | $ 0
Maturity Date Extension |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 6 | 2
Pre-Modification Outstanding Recorded Investment | $ 1,341 | $ 851
Post-Modification Outstanding Recorded Investment | 1,320 | 836
Total Difference in Recorded Investment | $ (21) | $ (15)
Maturity Date Extension | Commercial and Industrial |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 2 | 1
Pre-Modification Outstanding Recorded Investment | $ 625 | $ 780
Post-Modification Outstanding Recorded Investment | 605 | 765
Total Difference in Recorded Investment | $ (20) | $ (15)
Maturity Date Extension | Commercial Construction |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 1 | 0
Pre-Modification Outstanding Recorded Investment | $ 33 | $ 0
Post-Modification Outstanding Recorded Investment | 33 | 0
Total Difference in Recorded Investment | $ 0 | $ 0
Maturity Date Extension | Residential Mortgage |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 1 | 0
Pre-Modification Outstanding Recorded Investment | $ 483 | $ 0
Post-Modification Outstanding Recorded Investment | 483 | 0
Total Difference in Recorded Investment | $ 0 | $ 0
Maturity Date Extension | Home Equity |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Loans | contract | 2 | 1
Pre-Modification Outstanding Recorded Investment | $ 200 | $ 71
Post-Modification Outstanding Recorded Investment | 199 | 71
Total Difference in Recorded Investment | $ (1) | $ 0

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