SEGMENT INFORMATION - Long-live Assets by Geographic Area (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total long-lived assets	$ 735	$ 934
United States
Segment Reporting Information [Line Items]
Total long-lived assets	379	521
Hong Kong
Segment Reporting Information [Line Items]
Total long-lived assets	135	145
China
Segment Reporting Information [Line Items]
Total long-lived assets	57	61
Other foreign countries
Segment Reporting Information [Line Items]
Total long-lived assets	$ 164	$ 207