LOANS AND SERVICING - Loans modified and classified as troubled debt restructures (Details)	12 Months Ended
Dec. 31, 2016 USD ($) security loan	Dec. 31, 2015 USD ($) security loan person
Loans modified and classified as troubled debt restructures
Number of relationships with TDR loans \| loan		2
Loan modifications	$ 0
Non-accrual Loans	953,000	$ 776,000
Loans receivable	$ 279,492,000	$ 256,014,000
Number of TDRs in default of their modified terms \| security	0	0
Commitments to lend additional funds to borrowers with modified loans	$ 0	$ 0
Residential loans:
Loans modified and classified as troubled debt restructures
Number of loans \| loan	2	0
Loans receivable	$ 106,069,000	$ 104,735,000
Post-modification balance in recorded investment	671,000
One- to four- family, residential loans
Loans modified and classified as troubled debt restructures
Non-accrual Loans	755,000	776,000
Loans receivable	90,190,000	$ 86,472,000
Number of individuals guaranteeing the loans \| person		1
Pre-modification balance in recorded investment		$ 606,000
Post-modification balance in recorded investment		$ 606,000
Term of debt instrument		24 months
Home equity loans and lines of credit
Loans modified and classified as troubled debt restructures
Non-accrual Loans	198,000
Loans receivable	15,879,000	$ 18,263,000
Percentage of proceeds, tdr		100.00%
Post-modification balance in recorded investment		$ 80,000
Term of debt instrument		24 months
Commercial loans:
Loans modified and classified as troubled debt restructures
Loans receivable	148,087,000	$ 130,664,000
One-to-four family investment property
Loans modified and classified as troubled debt restructures
Loans receivable	13,081,000	15,255,000
Multi-family real estate
Loans modified and classified as troubled debt restructures
Loans receivable	30,748,000	30,709,000
Commercial real estate
Loans modified and classified as troubled debt restructures
Loans receivable	83,583,000	$ 67,152,000
Commercial business loan
Loans modified and classified as troubled debt restructures
Number of loans \| loan		2
Loans receivable	20,675,000	$ 17,548,000
Number of individuals guaranteeing the loans \| person		2
Sale of loans receivable		$ 100,000
Number of loan modifications that resulted in the classification of TDR \| loan		2
Pre-modification balance in recorded investment		$ 135,000
Construction loans
Loans modified and classified as troubled debt restructures
Loans receivable	25,154,000	20,378,000
One-to-four family, construction loans
Loans modified and classified as troubled debt restructures
Loans receivable	12,599,000	12,967,000
Multi-family
Loans modified and classified as troubled debt restructures
Loans receivable	5,725,000	1,486,000
Non-residential
Loans modified and classified as troubled debt restructures
Loans receivable	6,830,000	5,925,000
Consumer
Loans modified and classified as troubled debt restructures
Loans receivable	$ 182,000	237,000
Commercial portfolio segment
Loans modified and classified as troubled debt restructures
Loans receivable		235,000
Commercial business loan one
Loans modified and classified as troubled debt restructures
Proceeds from loans by payment of guarantor		23,000
Allowances for credit losses		22,000
Pre-modification balance in recorded investment		45,000
Post-modification balance in recorded investment		0
Commercial business loan two
Loans modified and classified as troubled debt restructures
Post-modification balance in recorded investment		$ 90,000

Commitments to lend additional funds to borrowers with modified loans.

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Represents the number of individuals guaranteeing the contracts in financing receivables.

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Represents the number of contracts in financing receivables.

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Represents the number of relationships the reporting entity has with customers who have loans that have been modified in troubled debt restructurings.

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Represents the percentage of net proceeds received by the reporting entity for the outstanding principal balance of the TDR loan under the Forbearance Agreement.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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A valuation allowance for financing receivables that are expected to be uncollectible.

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

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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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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

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The cash inflow from collection of repayments from borrowers on loans that are held with the intention to resell in the near future; includes loans that are not mortgages.

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The cash inflow associated with the sale of loans receivables arising from the financing of goods and services.

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