SECURITIES - Composition of Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Amortized cost (1)
Available-for-sale
U.S. Treasury notes	$ 9,998	$ 2,499
U.S. Government Agency notes		498
Municipal bonds	20,459	29,752
Mortgage-backed securities, U.S. Government agencies and U.S. Government-sponsored enterprises	38,220	31,900
Collateralized mortgage obligations, U.S. Government Agencies	1,732	2,002
Collateralized mortgage obligations, Non-agency	3,928	4,487
SBA bonds	2,628	3,065
CRA mutual funds	774	766
Corporate bonds	1,000
Preferred stock	20	20
Total securities available-for-sale	78,759	74,989
Non-marketable securities
Federal Home Loan Bank of Boston stock	3,436	3,176
Gross unrealized gains
Available-for-sale
U.S. Treasury notes	17	42
U.S. Government Agency notes
Municipal bonds	490	633
Mortgage-backed securities, U.S. Government agencies and U.S. Government-sponsored enterprises	430	385
Collateralized mortgage obligations, U.S. Government Agencies	8	12
Collateralized mortgage obligations, Non-agency	395	468
SBA bonds	26	31
CRA mutual funds	14
Corporate bonds
Preferred stock	322	226
Total securities available-for-sale	1,702	1,797
Non-marketable securities
Federal Home Loan Bank of Boston stock
Gross unrealized losses
Available-for-sale
U.S. Treasury notes
U.S. Government Agency notes
Municipal bonds
Mortgage-backed securities, U.S. Government agencies and U.S. Government-sponsored enterprises	(9)	(83)
Collateralized mortgage obligations, U.S. Government Agencies
Collateralized mortgage obligations, Non-agency	(11)	(7)
SBA bonds
CRA mutual funds		(2)
Corporate bonds	(3)
Preferred stock
Total securities available-for-sale	(23)	(92)
Non-marketable securities
Federal Home Loan Bank of Boston stock
Fair value
Available-for-sale
U.S. Treasury notes	10,015	2,541
U.S. Government Agency notes		498
Municipal bonds	20,949	30,385
Mortgage-backed securities, U.S. Government agencies and U.S. Government-sponsored enterprises	38,641	32,202
Collateralized mortgage obligations, U.S. Government Agencies	1,740	2,014
Collateralized mortgage obligations, Non-agency	4,312	4,948
SBA bonds	2,654	3,096
CRA mutual funds	788	764
Corporate bonds	997
Preferred stock	342	246
Total securities available-for-sale	80,438	76,694
Non-marketable securities
Federal Home Loan Bank of Boston stock	$ 3,436	$ 3,176

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Investments in notes or bonds that are collateralized by a specific group of underlying assets owned by the issuer of the notes or bonds which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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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 securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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For an unclassified balance sheet, this item represents investments in common and preferred stocks and other forms of securities that provide ownership interests in a corporation.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Bonds or similar securities issued by state, city, or local governments or the agencies operated by state, city, or local governments which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Carrying value as of the balance sheet date of the portion of long-term, collateralized debt obligations due within one year or the operating cycle, if longer. Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Debt securities issued by a United States government agency such as Government National Mortgage Association (Ginnie Mae), Federal Home Loan Mortgage Corporation (Freddie Mac), and Federal National Mortgage Association (Fannie Mae), which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Debt (bills, notes or bonds) that are issued by the government of the United States which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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