REVENUE RECOGNITION - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Total revenue	$ 145,378	$ 216,887
Revenue from Contract with Customer, Product and Service Benchmark | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Total revenue	145,378	216,887
Revenue from Contract with Customer, Product and Service Benchmark | Customer Concentration Risk | Firm fixed-price
Disaggregation of Revenue [Line Items]
Total revenue	$ 114,188	$ 179,803
Concentration risk, percentage	79.00%	83.00%
Revenue from Contract with Customer, Product and Service Benchmark | Customer Concentration Risk | Time-and-materials
Disaggregation of Revenue [Line Items]
Total revenue	$ 13,535	$ 12,963
Concentration risk, percentage	9.00%	6.00%
Revenue from Contract with Customer, Product and Service Benchmark | Customer Concentration Risk | Cost plus fixed-fee
Disaggregation of Revenue [Line Items]
Total revenue	$ 17,655	$ 24,121
Concentration risk, percentage	12.00%	11.00%
Federal government | Revenue from Contract with Customer, Product and Service Benchmark | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Total revenue	$ 131,143	$ 205,538
Concentration risk, percentage	90.00%	95.00%
State & local government, and commercial | Revenue from Contract with Customer, Product and Service Benchmark | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Total revenue	$ 14,235	$ 11,349
Concentration risk, percentage	10.00%	5.00%
U.S. Department of Defense ("DoD") | Revenue from Contract with Customer, Product and Service Benchmark | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration risk, percentage	64.00%	74.00%