SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Securities sold under agreements to repurchase
Securities sold under agreements to repurchase	$ 539	$ 877
Carrying amount of U.S. GSE residential collateralized mortgage obligations and U.S. GSE residential mortgage-backed securities	2,400	$ 1,800
First quarter of 2019
Securities sold under agreements to repurchase
Securities sold under agreements to repurchase	$ 500
U.S. GSE residential collateralized mortgage obligations
Securities sold under agreements to repurchase
Percentage of investment securities held as collateral	18.00%	52.00%
U.S. GSE residential mortgage-backed securities
Securities sold under agreements to repurchase
Percentage of investment securities held as collateral	82.00%	48.00%

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
Balance Type:	credit
Period Type:	instant