REVENUE AND RECEIVABLES - Timing of Revenue Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Total revenue	$ 709,880	$ 677,953	$ 565,541
Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	674,735	633,816	508,180
Goods and services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	35,145	44,137	57,361
US Telecom | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	326,966	301,309	188,405
US Telecom | Goods and services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	18,059	29,203	46,433
International Telecom | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	347,769	332,507	319,357
International Telecom | Goods and services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	$ 17,086	$ 14,934	10,928
Solar | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue			$ 418