SECURITIES - Aggreggate fair value and gross unrealized loss of securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Less Than 12 Months, Fair value
Available-for-sale
U.S. Government Agency notes
Municipal bonds	1,060	6,273
Mortgage-backed securities: U.S. Government agencies and U.S. Government- sponsored enterprises	2,808	5,781
Collateralized mortgage obligations: U.S. Government agencies		1,438
Corporate bonds	714
Total temporarily impaired securities	4,582	13,492
Less Than 12 Months, Unrealized losses
Available-for-sale
U.S. Government Agency notes
Municipal bonds	3	73
Mortgage-backed securities: U.S. Government agencies and U.S. Government- sponsored enterprises	30	22
Collateralized mortgage obligations: U.S. Government agencies		10
Corporate bonds	36
Total temporarily impaired securities	69	105
12 Months or Longer, Fair value
Available-for-sale
U.S. Government Agency notes	126	195
Municipal bonds
Mortgage-backed securities: U.S. Government agencies and U.S. Government- sponsored enterprises	108	704
Collateralized mortgage obligations: U.S. Government agencies
Corporate bonds
Total temporarily impaired securities	234	899
12 Months or Longer, Unrealized losses
Available-for-sale
U.S. Government Agency notes	1	1
Municipal bonds
Mortgage-backed securities: U.S. Government agencies and U.S. Government- sponsored enterprises	1	2
Collateralized mortgage obligations: U.S. Government agencies
Corporate bonds
Total temporarily impaired securities	2	3
Total, Fair value
Available-for-sale
U.S. Government Agency notes	126	195
Municipal bonds	1,060	6,273
Mortgage-backed securities: U.S. Government agencies and U.S. Government- sponsored enterprises	2,916	6,485
Collateralized mortgage obligations: U.S. Government agencies		1,438
Corporate bonds	714
Total temporarily impaired securities	4,816	14,391
Total, Unrealized losses
Available-for-sale
U.S. Government Agency notes	1	1
Municipal bonds	3	73
Mortgage-backed securities: U.S. Government agencies and U.S. Government- sponsored enterprises	31	24
Collateralized mortgage obligations: U.S. Government agencies		10
Corporate bonds	36
Total temporarily impaired securities	$ 71	$ 108

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 9A
-URI http://asc.fasb.org/extlink&oid=121553693&loc=SL6284427-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669686-108580

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- Definition

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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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969

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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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- Definition

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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- Definition

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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