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Loans and Loans Held for Sale - Summary of Nonperforming Assets of Defaulted TDRs (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 USD ($) contract loan | Dec. 31, 2014 USD ($) contract
Financing Receivable, Modifications [Line Items] |  |
Number of loan modified | loan | 39 |
Number of Defaults | contract | 0 | 3
Recorded Investment | $ 0 | $ 64
Commercial Real Estate |  |
Financing Receivable, Modifications [Line Items] |  |
Number of loan modified | loan | 8 |
Loans modified not considered to be troubled debt restructuring | $ 6,100 |
Number of Defaults | contract | 0 | 0
Recorded Investment | $ 0 | $ 0
Commercial and Industrial |  |
Financing Receivable, Modifications [Line Items] |  |
Number of loan modified | loan | 11 |
Loans modified not considered to be troubled debt restructuring | $ 7,800 |
Number of Defaults | contract | 0 | 0
Recorded Investment | $ 0 | $ 0
Commercial Construction |  |
Financing Receivable, Modifications [Line Items] |  |
Number of loan modified | loan | 14 |
Loans modified not considered to be troubled debt restructuring | $ 8,500 |
Residential Real Estate |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Defaults | contract | 0 | 1
Recorded Investment | $ 0 | $ 20
Home Equity |  |
Financing Receivable, Modifications [Line Items] |  |
Number of loan modified | loan | 4 |
Loans modified not considered to be troubled debt restructuring | $ 400 |
Number of Defaults | contract | 0 | 2
Recorded Investment | $ 0 | $ 44
Residential Mortgage |  |
Financing Receivable, Modifications [Line Items] |  |
Number of loan modified | loan | 2 |
Loans modified not considered to be troubled debt restructuring | $ 100 |

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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524 + Details
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