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Derivative Instruments and Hedging Activities - Amount of Gain or Loss Recognized in Income on Derivatives (Detail) - Not Designated as Hedging Instruments - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total Derivative Gain (Loss) | $ 70 | $ 36 | $ (474)
Interest Rate Swap Contracts-Commercial Loans |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total Derivative Gain (Loss) | (8) | (24) | (174)
Interest Rate Lock Commitments-Mortgage Loans |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total Derivative Gain (Loss) | 26 | 150 | (382)
Forward Sale Contracts-Mortgage Loans |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total Derivative Gain (Loss) | $ 52 | $ (90) | $ 82

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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