UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Statement [Abstract]
REVENUES	$ 139,910	$ 136,224	$ 274,590	$ 270,041
COST OF REVENUES (exclusive of depreciation and amortization shown below)	90,429	92,104	178,815	187,420
SELLING, GENERAL AND ADMINISTRATIVE EXPENSE	46,456	27,366	88,263	52,366
FAIR VALUE CHANGES IN BUSINESS ACQUISITIONS CONTINGENCIES	(3,510)	12,971	(3,531)	24,035
DEPRECIATION AND AMORTIZATION	12,280	9,878	24,424	21,674
LOSS FROM OPERATIONS	(5,745)	(6,095)	(13,381)	(15,454)
OTHER (EXPENSE) INCOME
Other income (expense)	343	(511)	2,804	(1,393)
Interest expense—net	(1,518)	(6,798)	(2,610)	(9,486)
Total other (expense) income - net	(1,175)	(7,309)	194	(10,879)
LOSS BEFORE EXPENSE (BENEFIT) FROM INCOME TAXES	(6,920)	(13,404)	(13,187)	(26,333)
INCOME TAX EXPENSE (BENEFIT)	831	(256)	2,100	(254)
NET LOSS	(7,751)	(13,148)	(15,287)	(26,079)
EQUITY ADJUSTMENT FROM FOREIGN CURRENCY TRANSLATION	(84)	28	(3)	57
COMPREHENSIVE LOSS	(7,835)	(13,120)	(15,290)	(26,022)
CONVERTIBLE AND REDEEMABLE SERIES A-2 PREFERRED STOCK DIVIDEND	(4,100)	(4,100)	(8,200)	(8,200)
NET LOSS ATTRIBUTABLE TO COMMON STOCKHOLDERS	$ (11,851)	$ (17,248)	$ (23,487)	$ (34,279)
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING— BASIC AND DILUTED	29,678	26,056	29,670	25,586
NET LOSS PER SHARE ATTRIBUTABLE TO COMMON STOCKHOLDERS - BASIC AND DILUTED	$ (0.40)	$ (0.66)	$ (0.79)	$ (1.34)