Consolidated Statements of Operations - USD ($)		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Revenues	[1]	$ 874,553,000	$ 852,539,000	$ 1,163,314,000
Operating expenses		660,118,000	613,828,000	835,570,000
Gross margin		214,435,000	238,711,000	327,744,000
Selling, general and administrative expenses		272,869,000	260,920,000	328,214,000
Restructuring and other related charges, net (see Note 17)		2,916,000	3,365,000	1,676,000
Goodwill impairment charge (see Note 8)		64,632,000	191,788,000	0
Operating loss		(125,982,000)	(217,362,000)	(2,146,000)
Interest expense, net		(46,308,000)	(29,818,000)	(29,713,000)
Loss on warrants		(59,000)	0	0
Loss on debt extinguishment and modification		0	(2,224,000)	(279,000)
Other income (expense), net		(2,461,000)	(2,514,000)	(715,000)
Loss before income taxes		(174,810,000)	(251,918,000)	(32,853,000)
Benefit (provision) for income taxes (see Note 10)		(11,209,000)	14,715,000	436,000
Net loss		$ (186,019,000)	$ (237,203,000)	$ (32,417,000)
Loss per common share:
Basic (in USD per share)		$ (6.01)	$ (7.74)	$ (1.07)
Diluted (in USD per share)		$ (6.01)	$ (7.74)	$ (1.07)

[1] Revenues attributable to individual countries/geographic areas are based on the country of domicile of the legal entity that performs the work.