RECEIVABLES, CONTRACT ASSETS, AND DEFERRED REVENUE- Contract Effective (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020 USD ($)
Receivables [Abstract]
2020	$ 75,893
2019	100,671
2018	46,700
2017	38,899
2016 and prior	45,398
Unbilled Revenue Total	$ 307,561
2020	25.00%
2019	32.00%
2018	15.00%
2017	13.00%
2016 and prior	15.00%
Total Percentage of Unbilled Revenue	100.00%
Revenue recognized during the period that was included in deferred revenue	$ 136,800