LOANS AND SERVICING - Analysis of impaired loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Recorded Investment
Impaired loans without a valuation allowance	$ 1,646	$ 322
Impaired loans with a valuation allowance	400	317
Unpaid Principal Balance
Impaired loans without a valuation allowance	1,646	322
Impaired loans with a valuation allowance	400	317
Related Allowance
Impaired loans with a valuation allowance	14	7
Average Recorded Investment
Impaired loans without a valuation allowance	653	326
Impaired loans with a valuation allowance	369	868
Interest Income Recognized
Impaired loans without a valuation allowance	40	19
Impaired loans with a valuation allowance	20	24
One- to four- family, residential loans
Recorded Investment
Impaired loans without a valuation allowance	1,255
Impaired loans with a valuation allowance	312	317
Unpaid Principal Balance
Impaired loans without a valuation allowance	1,255
Impaired loans with a valuation allowance	312	317
Related Allowance
Impaired loans with a valuation allowance	7	7
Average Recorded Investment
Impaired loans without a valuation allowance	236
Impaired loans with a valuation allowance	314	319
Interest Income Recognized
Impaired loans without a valuation allowance	12
Impaired loans with a valuation allowance	16	16
Home equity loans and lines of credit
Recorded Investment
Impaired loans without a valuation allowance	104	27
Unpaid Principal Balance
Impaired loans without a valuation allowance	104	27
Related Allowance
Impaired loans without a valuation allowance		28
Average Recorded Investment
Impaired loans without a valuation allowance	51	1
Impaired loans with a valuation allowance		123
Interest Income Recognized
Impaired loans without a valuation allowance	2
Commercial real estate
Recorded Investment
Impaired loans without a valuation allowance	287	295
Unpaid Principal Balance
Impaired loans without a valuation allowance	287	295
Average Recorded Investment
Impaired loans without a valuation allowance	292	298
Impaired loans with a valuation allowance		426
Interest Income Recognized
Impaired loans without a valuation allowance	17	18
Impaired loans with a valuation allowance		$ 8
Commercial business loan
Average Recorded Investment
Impaired loans without a valuation allowance	74
Interest Income Recognized
Impaired loans without a valuation allowance	9
One-to-four family investment property
Recorded Investment
Impaired loans with a valuation allowance	88
Unpaid Principal Balance
Impaired loans with a valuation allowance	88
Related Allowance
Impaired loans with a valuation allowance	7
Average Recorded Investment
Impaired loans with a valuation allowance	55
Interest Income Recognized
Impaired loans with a valuation allowance	$ 4

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Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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