CONCENTRATION OF RISK - Revenues by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Concentration Risk [Line Items]
Revenues	$ 136,561	$ 129,660	$ 287,031	$ 263,660
South Korea [Member]
Concentration Risk [Line Items]
Revenues	79,096	86,324	168,783	154,299
China [Member]
Concentration Risk [Line Items]
Revenues	51,180	36,308	106,580	96,812
Japan [Member]
Concentration Risk [Line Items]
Revenues	1,392	2,001	2,445	3,316
Other Non-U.S. Locations [Member]
Concentration Risk [Line Items]
Revenues	715	895	1,015	1,720
Total Non-U.S. Locations [Member]
Concentration Risk [Line Items]
Revenues	132,383	125,528	278,823	256,147
United States [Member]
Concentration Risk [Line Items]
Revenues	$ 4,178	$ 4,132	$ 8,208	$ 7,513