REVENUE - Schedule of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Revenue	$ 153,120	$ 178,453
Service revenue
Disaggregation of Revenue [Line Items]
Revenue	144,496	170,613
Reimbursable expenses
Disaggregation of Revenue [Line Items]
Revenue	8,039	6,555
Non-controlling interests
Disaggregation of Revenue [Line Items]
Revenue	$ 585	$ 1,285