SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Securities sold under agreements to repurchase
Repurchase agreements	$ 999	$ 539
Carrying amount of U.S. GSE residential collateralized mortgage obligations and U.S. GSE residential mortgage-backed securities	2,100	$ 2,400
First quarter of 2020
Securities sold under agreements to repurchase
Repurchase agreements	$ 1,000
U.S. GSE residential collateralized mortgage obligations
Securities sold under agreements to repurchase
Percentage of investment securities held as collateral	17.00%	18.00%
U.S. GSE residential mortgage-backed securities
Securities sold under agreements to repurchase
Percentage of investment securities held as collateral	83.00%	82.00%

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant