REVENUE FROM CONTRACTS WITH CUSTOMERS - Disaggregation of revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Net revenues	$ 96,708	$ 82,631
Supplemental Benefit Services
Disaggregation of Revenue [Line Items]
Net revenues	50,228	39,104
Health Plan Management
Disaggregation of Revenue [Line Items]
Net revenues	25,862	23,942
Consulting Services
Disaggregation of Revenue [Line Items]
Net revenues	15,784	14,087
Software Services
Disaggregation of Revenue [Line Items]
Net revenues	2,276	2,730
Data Analytics
Disaggregation of Revenue [Line Items]
Net revenues	2,558	2,768
Technology Enabled Solutions
Disaggregation of Revenue [Line Items]
Net revenues	83,166	69,582
Technology Enabled Solutions | Supplemental Benefit Services
Disaggregation of Revenue [Line Items]
Net revenues	50,228	39,104
Technology Enabled Solutions | Health Plan Management
Disaggregation of Revenue [Line Items]
Net revenues	25,862	23,942
Technology Enabled Solutions | Consulting Services
Disaggregation of Revenue [Line Items]
Net revenues	2,327	1,038
Technology Enabled Solutions | Software Services
Disaggregation of Revenue [Line Items]
Net revenues	2,191	2,730
Technology Enabled Solutions | Data Analytics
Disaggregation of Revenue [Line Items]
Net revenues	2,558	2,768
Advisory Services
Disaggregation of Revenue [Line Items]
Net revenues	13,542	13,049
Advisory Services | Supplemental Benefit Services
Disaggregation of Revenue [Line Items]
Net revenues	0	0
Advisory Services | Health Plan Management
Disaggregation of Revenue [Line Items]
Net revenues	0	0
Advisory Services | Consulting Services
Disaggregation of Revenue [Line Items]
Net revenues	13,457	13,049
Advisory Services | Software Services
Disaggregation of Revenue [Line Items]
Net revenues	85	0
Advisory Services | Data Analytics
Disaggregation of Revenue [Line Items]
Net revenues	$ 0	$ 0