LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES - Allowance for credit losses (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2020 USD ($) borrower	Jun. 30, 2019 USD ($) borrower	Dec. 31, 2019 USD ($)
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Average loans	$ 284,168	$ 295,425
Net charge-offs to average loans (annualized)	0.02%	0.24%
Number of borrowers \| borrower	20	39
Loans charged off	$ 171	$ 435	$ 616
Outstanding commitments	31,800	25,300
Unfunded commitments
Beginning balance	37	35	35
Reduction of unfunded reserve		(23)
Provisions charged to operations	60
Ending balance	$ 97	$ 12	$ 37

Amount of writeoff of financing receivable, charged against allowance for credit loss.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 55
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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