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Loans and Loans Held for Sale - Restructured Loans for Periods Presented (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | $ 6,338 | $ 4,777
Performing TDRs |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 23,955 | 36,983
Performing TDRs | Commercial Real Estate |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 6,822 | 16,939
Performing TDRs | Commercial and Industrial |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 6,321 | 8,074
Performing TDRs | Commercial Construction |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 5,013 | 5,736
Performing TDRs | Residential Mortgage |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 2,590 | 2,839
Performing TDRs | Home Equity |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 3,184 | 3,342
Performing TDRs | Installment and Other Consumer |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 25 | 53
Nonperforming TDRs |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 7,659 | 5,436
Nonperforming TDRs | Commercial Real Estate |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 3,548 | 2,180
Nonperforming TDRs | Commercial and Industrial |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 1,570 | 356
Nonperforming TDRs | Commercial Construction |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 1,265 | 1,869
Nonperforming TDRs | Residential Mortgage |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 665 | 459
Nonperforming TDRs | Home Equity |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 523 | 562
Nonperforming TDRs | Installment and Other Consumer |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 88 | 10
Total TDRs |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 31,614 | 42,419
Total TDRs | Commercial Real Estate |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 10,370 | 19,119
Total TDRs | Commercial and Industrial |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 7,891 | 8,430
Total TDRs | Commercial Construction |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 6,278 | 7,605
Total TDRs | Residential Mortgage |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 3,255 | 3,298
Total TDRs | Home Equity |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | 3,707 | 3,904
Total TDRs | Installment and Other Consumer |  |
Financing Receivable, Modifications [Line Items] |  |
Restructured loans | $ 113 | $ 63

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