ALLOWANCE FOR LOAN LOSSES - Summary of TDR Pre- and Post-modification Outstanding Recorded Investments by Loan Categories (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) Contract SecurityLoan	Dec. 31, 2016 USD ($) Contract SecurityLoan
Financing Receivable Modifications [Line Items]
Number of Contracts \| SecurityLoan	18	18
Pre- Modification Outstanding Recorded Investment	$ 5	$ 436
Post- Modification Outstanding Recorded Investment	$ 5	$ 436
Mortgage loans on real estate \| 1-4 Family
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	0	9
Pre- Modification Outstanding Recorded Investment	$ 0	$ 436
Post- Modification Outstanding Recorded Investment	$ 0	$ 436
Consumer
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	1	0
Pre- Modification Outstanding Recorded Investment	$ 5	$ 0
Post- Modification Outstanding Recorded Investment	$ 5	$ 0

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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