FAIR VALUE OF ASSETS AND LIABILITIES - Carrying value and estimated fair values of financial instruments (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Carrying value
Financial Assets
Cash and cash equivalents	$ 52,900	$ 36,105
Securities available-for-sale	81,179	91,312
Federal Home Loan Bank stock	3,515	3,515
Loans held-for-sale	328	568
Loans receivable, net	676,734	673,330
Accrued interest receivable	2,356	2,334
Financial Liabilities
Demand (non-interest-bearing)	163,387	161,386
Demand (interest-bearing)	115,099	117,169
Money market	173,492	174,274
Savings and other	131,794	121,387
Certificates of deposit	141,138	141,210
Deposits	724,910	715,426
Repurchase agreements	3,278	4,163
FHLBB advances	28,403	28,813
Capital lease liability	423	424
Accrued interest payable	166	166
Estimated fair value
Financial Assets
Cash and cash equivalents	52,900	36,105
Securities available-for-sale	81,179	91,312
Federal Home Loan Bank stock	3,515	3,515
Loans held-for-sale	332	572
Loans receivable, net	683,921	683,845
Accrued interest receivable	2,356	2,334
Financial Liabilities
Demand (non-interest-bearing)	163,387	161,386
Demand (interest-bearing)	115,099	117,169
Money market	173,492	174,274
Savings and other	131,794	121,387
Certificates of deposit	142,313	142,261
Deposits	726,085	716,477
Repurchase agreements	3,278	4,163
FHLBB advances	30,175	30,626
Capital lease liability	931	929
Accrued interest payable	166	166
Fair Value Measurements Using - Level 1
Financial Assets
Cash and cash equivalents	52,900	36,105
Securities available-for-sale	369	327
Federal Home Loan Bank stock
Loans held-for-sale
Loans receivable, net
Accrued interest receivable
Financial Liabilities
Demand (non-interest-bearing)
Demand (interest-bearing)
Money market
Savings and other
Certificates of deposit
Deposits
Repurchase agreements
FHLBB advances
Capital lease liability
Accrued interest payable
Fair Value Measurements Using - Level 2
Financial Assets
Cash and cash equivalents
Securities available-for-sale	80,810	90,985
Federal Home Loan Bank stock	3,515	3,515
Loans held-for-sale
Loans receivable, net
Accrued interest receivable
Financial Liabilities
Demand (non-interest-bearing)
Demand (interest-bearing)
Money market
Savings and other
Certificates of deposit
Deposits
Repurchase agreements
FHLBB advances
Capital lease liability
Accrued interest payable
Fair Value Measurements Using - Level 3
Financial Assets
Cash and cash equivalents
Securities available-for-sale
Federal Home Loan Bank stock
Loans held-for-sale	332	572
Loans receivable, net	683,921	683,845
Accrued interest receivable	2,356	2,334
Financial Liabilities
Demand (non-interest-bearing)	163,387	161,386
Demand (interest-bearing)	115,099	117,169
Money market	173,492	174,274
Savings and other	131,794	121,387
Certificates of deposit	142,313	142,261
Deposits	726,085	716,477
Repurchase agreements	3,278	4,163
FHLBB advances	30,175	30,626
Capital lease liability	931	929
Accrued interest payable	$ 166	$ 166

Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Amount of obligations incurred and payable, pertaining to costs that are statutory in nature, incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include, but not limited to, taxes, interest, rent and utilities. Also includes the aggregate carrying amount of liabilities not separately disclosed.

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Fair value of Federal Home Loan Bank (FHLBank) advances carried under the fair value option.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount of capital lease obligation, assumed at the acquisition date.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Amount of interest-bearing domestic certificate of deposit liabilities.

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Amount of money in interest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

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Amount of interest-bearing domestic money market demand account deposit liabilities.

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Amount of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Amount of money in noninterest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

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An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt 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. This amount does not include amounts related to receivables held-for-sale.

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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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