COMMITMENTS AND CONTINGENCIES - Maturity analysis of operating lease liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
COMMITMENTS AND CONTINGENCIES
Within one year	$ 130	$ 148
After one but within two years	102	106
After two but within three years	68	86
After three but within four years	68	68
After four but within five years	68	68
After five years	2,292	2,326
Total undiscounted cash flows	2,728	2,802
Discount on cash flows	(1,172)	(1,139)
Total lease liability	$ 1,556	$ 1,663

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
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