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DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Effect of Derivative Instruments on Statement of Income (Loss) (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Economic undesignated hedges: |  |  |
Total gain (loss) on derivatives | $ 187 | $ (78) | $ 164
Interest Income Loans [Member] | Interest Rate Swap [Member] |  |  |
Economic undesignated hedges: |  |  |
Total gain (loss) on derivatives | 0 | 0 | 0
Interest Income Loans [Member] | Interest Rate Cap [Member] |  |  |
Economic undesignated hedges: |  |  |
Total gain (loss) on derivatives | (2) | 0 | 139
Mortgage Banking Activities [Member] | Forward Contracts [Member] |  |  |
Economic undesignated hedges: |  |  |
Total gain (loss) on derivatives | $ 189 | $ (78) | $ 25

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- Definition Undesignated Fair Value Hedge [Abstract] + References No definition available. + Details
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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=84234895&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=84234895&loc=SL5624171-113959 + Details
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