SECURITIES - Aggreggate fair value and gross unrealized loss of securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Less Than 12 Months, Fair value
Available-for-sale
U.S. Government Agency notes	$ 4,963
Municipal bonds	1,674	$ 479
Mortgage-backed securities	12,694	15,914
Collateralized mortgage obligations, U.S. Government agencies	13,546	9,317
Collateralized mortgage obligations, Non-agency	94
SBA bonds	25,346	8,519
Corporate bonds		1,491
Total temporarily impaired securities	58,317	35,720
Other than temporarily impaired securities, Collateralized mortgage obligations, Non-agency		101
Total temporarily impaired and other-than-temporarily impaired securities	58,317	35,821
Less Than 12 Months, Unrealized losses
Available-for-sale
U.S. Government Agency notes	28
Municipal bonds	7	1
Mortgage-backed securities	210	99
Collateralized mortgage obligations, U.S. Government agencies	225	87
Collateralized mortgage obligations, Non-agency	4
SBA bonds	643	20
Corporate bonds		9
Total temporarily impaired securities	1,117	216
Other than temporarily impaired securities, Collateralized mortgage obligations, Non-agency		14
Total temporarily impaired and other-than-temporarily impaired securities	1,117	230
12 Months or Longer, Fair value
Available-for-sale
U.S. Government Agency notes
Municipal bonds
Mortgage-backed securities	19,584	17,892
Collateralized mortgage obligations, U.S. Government agencies	3,949
Collateralized mortgage obligations, Non-agency		77
SBA bonds	2,428
Corporate bonds
Total temporarily impaired securities	25,961	17,969
Other than temporarily impaired securities, Collateralized mortgage obligations, Non-agency	75
Total temporarily impaired and other-than-temporarily impaired securities	26,036	17,969
12 Months or Longer, Unrealized losses
Available-for-sale
U.S. Government Agency notes
Municipal bonds
Mortgage-backed securities	257	168
Collateralized mortgage obligations, U.S. Government agencies	179
Collateralized mortgage obligations, Non-agency		3
SBA bonds	114
Corporate bonds
Total temporarily impaired securities	550	171
Other than temporarily impaired securities, Collateralized mortgage obligations, Non-agency	17
Total temporarily impaired and other-than-temporarily impaired securities	567	171
Total, Fair value
Available-for-sale
U.S. Government Agency notes	4,963
Municipal bonds	1,674	479
Mortgage-backed securities	32,278	33,806
Collateralized mortgage obligations, U.S. Government agencies	17,495	9,317
Collateralized mortgage obligations, Non-agency	94	77
SBA bonds	27,774	8,519
Corporate bonds		1,491
Total temporarily impaired securities	84,278	53,689
Other than temporarily impaired securities, Collateralized mortgage obligations, Non-agency	75	101
Total temporarily impaired and other-than-temporarily impaired securities	84,343	53,790
Total, Unrealized losses
Available-for-sale
U.S. Government Agency notes	28
Municipal bonds	7	1
Mortgage-backed securities	467	267
Collateralized mortgage obligations, U.S. Government agencies	404	87
Collateralized mortgage obligations, Non-agency	4	3
SBA bonds	757	20
Corporate bonds		9
Total temporarily impaired securities	1,667	387
Other than temporarily impaired securities, Collateralized mortgage obligations, Non-agency	17	14
Total temporarily impaired and other-than-temporarily impaired securities	$ 1,684	$ 401

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Accumulated other comprehensive loss related to portion of other than temporary impairment (OTTI) due to factors other than credit losses on debt securities categorized as available-for-sale that an entity does not intend to sell and which it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis of the debt security. The amount represented by this item is net of tax, as applicable.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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Total of accumulated other comprehensive loss related to that portion of other than temporary impairment (OTTI) due to factors other than credit losses on debt securities categorized either as available-for-sale or held-to-maturity that an entity does not intend to sell and which it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis of the debt security. The amount represented by this item is net of tax, as applicable.

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- Definition

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 securities that are debt instruments (corporate or municipal bonds) that typically have long-term nominal maturities for which the interest rate is reset through an auction process.

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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
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
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The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
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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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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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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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