SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, Basic and Diluted Net Income per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Numerator [Abstract]
Net income	$ 30,994	$ 27,076	$ 73,554	$ 36,381
Less: Net income attributable to non-controlling interests	5,315	6,072	13,905	8,927
Net income available to common stockholders, basic	25,679	21,004	59,649	27,454
Less: Dilutive effect arising from stock-based awards by ACM Shanghai	(461)	(321)	(1,338)	(465)
Net income available to common stockholders, diluted	$ 25,218	$ 20,683	$ 58,311	$ 26,989
Weighted average shares outstanding, basic (in shares)	60,219,218	59,360,790	59,953,144	59,123,895
Effect of dilutive securities (in shares)	5,231,723	6,251,875	4,880,907	6,505,378
Weighted average shares outstanding, diluted (in shares)	65,450,941	65,612,665	64,834,051	65,629,273
Net income per common share [Abstract]
Basic (in dollars per share)	$ 0.43	$ 0.35	$ 0.99	$ 0.46
Diluted (in dollars per share)	$ 0.39	$ 0.32	$ 0.90	$ 0.41
Incremental common shares attributable to dilutive effect of share-based payment arrangements (in shares)	1,757,605	1,993,050	4,099,228	1,897,050