LOANS AND SERVICING - Analysis of impaired loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Recorded Investment
Impaired loans without a valuation allowance	$ 2,103	$ 1,967
Impaired loans with a valuation allowance	85	85
Unpaid Principal Balance
Impaired loans without a valuation allowance	2,123	1,979
Impaired loans with a valuation allowance	85	85
Related Allowance
Impaired loans with a valuation allowance	7	7
Average Recorded Investment
Impaired loans without a valuation allowance	2,036	1,953
Impaired loans with a valuation allowance	85	87
Interest Income Recognized
Impaired loans without a valuation allowance	19	64
Impaired loans with a valuation allowance	1	4
One- to four- family, residential loans
Recorded Investment
Impaired loans without a valuation allowance	1,529	1,543
Unpaid Principal Balance
Impaired loans without a valuation allowance	1,549	1,555
Average Recorded Investment
Impaired loans without a valuation allowance	1,536	1,560
Interest Income Recognized
Impaired loans without a valuation allowance	14	42
Home equity loans and lines of credit
Recorded Investment
Impaired loans without a valuation allowance	296	143
Unpaid Principal Balance
Impaired loans without a valuation allowance	296	143
Average Recorded Investment
Impaired loans without a valuation allowance	220	109
Interest Income Recognized
Impaired loans without a valuation allowance	1	5
Commercial real estate
Recorded Investment
Impaired loans without a valuation allowance	278	281
Unpaid Principal Balance
Impaired loans without a valuation allowance	278	281
Average Recorded Investment
Impaired loans without a valuation allowance	280	284
Interest Income Recognized
Impaired loans without a valuation allowance	4	17
One-to-four family investment property
Recorded Investment
Impaired loans with a valuation allowance	85	85
Unpaid Principal Balance
Impaired loans with a valuation allowance	85	85
Related Allowance
Impaired loans with a valuation allowance	7	7
Average Recorded Investment
Impaired loans with a valuation allowance	85	87
Interest Income Recognized
Impaired loans with a valuation allowance	$ 1	$ 4

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Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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