SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Goodwill (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Goodwill from business combinations
Goodwill	$ 25,111	$ 25,111

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(10)(1))
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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