SECURITIES - Composition of Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Amortized cost (1)
Available-for-sale
U.S. Treasury notes		$ 2,499
U.S. Government Agency notes		498
Municipal bonds	$ 18,252	29,752
Mortgage-backed securities, U.S. Government agencies and U.S. Government-sponsored enterprises	47,881	31,900
Collateralized mortgage obligations, U.S. Government Agencies	1,596	2,002
Collateralized mortgage obligations, Non-agency	3,619	4,487
SBA bonds	2,268	3,065
CRA mutual funds	828	766
Corporate bonds	1,000
Preferred stock	20	20
Total securities available-for-sale	75,464	74,989
Non-marketable securities
Federal Home Loan Bank of Boston stock	2,937	3,176
Gross unrealized gains
Available-for-sale
U.S. Treasury notes		42
U.S. Government Agency notes
Municipal bonds	352	633
Mortgage-backed securities, U.S. Government agencies and U.S. Government-sponsored enterprises	372	385
Collateralized mortgage obligations, U.S. Government Agencies	8	12
Collateralized mortgage obligations, Non-agency	418	468
SBA bonds	18	31
CRA mutual funds	10
Corporate bonds	20
Preferred stock	221	226
Total securities available-for-sale	1,419	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	(77)	(83)
Collateralized mortgage obligations, U.S. Government Agencies
Collateralized mortgage obligations, Non-agency	(5)	(7)
SBA bonds
CRA mutual funds		(2)
Corporate bonds
Preferred stock
Total securities available-for-sale	(82)	(92)
Non-marketable securities
Federal Home Loan Bank of Boston stock
Fair value
Available-for-sale
U.S. Treasury notes		2,541
U.S. Government Agency notes		498
Municipal bonds	18,604	30,385
Mortgage-backed securities, U.S. Government agencies and U.S. Government-sponsored enterprises	48,176	32,202
Collateralized mortgage obligations, U.S. Government Agencies	1,604	2,014
Collateralized mortgage obligations, Non-agency	4,032	4,948
SBA bonds	2,286	3,096
CRA mutual funds	838	764
Corporate bonds	1,020
Preferred stock	241	246
Total securities available-for-sale	76,801	76,694
Non-marketable securities
Federal Home Loan Bank of Boston stock	$ 2,937	$ 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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-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
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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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