REVENUE FROM CONTRACTS WITH CUSTOMERS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregated Revenue Information [Abstract]
Revenue	$ 259,751	$ 156,624	$ 107,524
Mainland China [Member]
Disaggregated Revenue Information [Abstract]
Revenue	258,615	154,359	103,467
Oher Regions [Member]
Disaggregated Revenue Information [Abstract]
Revenue	1,136	2,265	4,057
Single Wafer Cleaning, Tahoe and Semi-Critical Cleaning Equipment [Member]
Disaggregated Revenue Information [Abstract]
Revenue	189,208	131,248	90,501
ECP (Front-end and Packaging), Furnace and Other Technologies [Member]
Disaggregated Revenue Information [Abstract]
Revenue	33,210	13,343	6,900
Advanced Packaging (Excluding ECP), Services & Spares [Member]
Disaggregated Revenue Information [Abstract]
Revenue	37,333	12,033	10,124
Wet Cleaning and Other Front-end Processing Tools [Member]
Disaggregated Revenue Information [Abstract]
Revenue	202,268	136,317	90,935
Advanced Packaging, Other Processing Tools, Services and Spares [Member]
Disaggregated Revenue Information [Abstract]
Revenue	$ 57,483	$ 20,307	$ 16,590