SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)
Revenues	$ 40,523	$ 39,860	$ 34,668	$ 33,498	$ 29,886	$ 29,555	$ 27,419	$ 24,200	$ 148,549	$ 111,060	$ 88,046
Costs of revenues	11,791	12,545	12,042	11,529	11,675	11,070	10,785	10,663	47,907	44,193	36,765
Net loss	$ 483	$ 1,385	$ (1,147)	$ (4,150)	$ (7,000)	$ (2,407)	$ (4,484)	$ (7,597)	$ (3,429)	$ (21,488)	$ (40,363)
Basic (in dollars per share)	$ 0.01	$ 0.04	$ (0.03)	$ (0.11)	$ (0.19)	$ (0.06)	$ (0.12)	$ (0.21)	$ (0.09)	$ (0.58)	$ (1.17)
Diluted (in dollars per share)	$ 0.01	$ 0.04	$ (0.03)	$ (0.11)	$ (0.19)	$ (0.06)	$ (0.12)	$ (0.21)	$ (0.09)	$ (0.58)	$ (1.17)