REVENUE RECOGNITION - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Revenue	$ 51,917	$ 34,461
RPO Recruitment
Disaggregation of Revenue [Line Items]
Revenue	25,260	12,386
Contracting
Disaggregation of Revenue [Line Items]
Revenue	$ 26,657	$ 22,075

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details