SEGMENT INFORMATION (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2023 USD ($) segment	Dec. 31, 2022 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment	1
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	$ 210,216	$ 144,321
Mainland China
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	196,597	140,481
Korea
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	12,300	3,830
United States
Geographic Areas, Long-Lived Assets [Abstract]
Long-lived assets	$ 1,319	$ 10