FAIR VALUE MEASUREMENTS - Carrying value and estimated fair values of financial instruments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Carrying value
Financial Assets
Cash and cash equivalents	$ 36,105	$ 12,711
Interest-bearing time deposits with other banks		738
Securities available-for-sale	91,312	94,491
Federal Home Loan Bank stock	3,515	5,340
Loans held-for-sale	568	173
Loans receivable, net	673,330	438,178
Accrued interest receivable	2,334	1,760
Financial Liabilities
Demand (non-interest-bearing)	161,386	84,677
Demand (interest-bearing)	117,169	81,932
Money market	174,274	120,550
Savings and other	121,387	107,171
Certificates of deposit	141,210	83,039
Deposits	715,426	477,369
Repurchase agreements	4,163	2,554
FHLBB advances	28,813	30,411
Capital lease liability	424	425
Accrued interest payable	166	140
Estimated fair value
Financial Assets
Cash and cash equivalents	36,105	12,711
Interest-bearing time deposits with other banks		738
Securities available-for-sale	91,312	94,491
Federal Home Loan Bank stock	3,515	5,340
Loans held-for-sale	572	175
Loans receivable, net	683,845	430,645
Accrued interest receivable	2,334	1,760
Financial Liabilities
Demand (non-interest-bearing)	161,386	84,677
Demand (interest-bearing)	117,169	81,932
Money market	174,274	120,550
Savings and other	121,387	107,171
Certificates of deposit	142,261	83,520
Deposits	716,477	477,850
Repurchase agreements	4,163	2,554
FHLBB advances	30,626	33,034
Capital lease liability	929	425
Accrued interest payable	166	140
Fair Value Measurements Using - Level 1
Financial Assets
Cash and cash equivalents	36,105	12,711
Interest-bearing time deposits with other banks
Securities available-for-sale	327	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		425
Accrued interest payable
Fair Value Measurements Using - Level 2
Financial Assets
Cash and cash equivalents
Interest-bearing time deposits with other banks
Securities available-for-sale	90,985	90,985
Federal Home Loan Bank stock	3,515	5,340
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
Interest-bearing time deposits with other banks		738
Securities available-for-sale
Federal Home Loan Bank stock
Loans held-for-sale	572	175
Loans receivable, net	683,845	430,645
Accrued interest receivable	2,334	1,760
Financial Liabilities
Demand (non-interest-bearing)	161,386	84,677
Demand (interest-bearing)	117,169	81,932
Money market	174,274	120,550
Savings and other	121,387	107,171
Certificates of deposit	142,261	83,520
Deposits	716,477	477,850
Repurchase agreements	4,163	2,554
FHLBB advances	30,626	33,034
Capital lease liability	929
Accrued interest payable	$ 166	$ 140

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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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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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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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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