Segment and Geographic Area Information - Revenue by segment information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) segment	Sep. 30, 2022 USD ($)
Segment information
Number of segments | segment			3
Revenue	$ 253,125	$ 264,038	$ 799,683	$ 810,206
Cost of revenue (exclusive of depreciation and amortization)	198,450	217,842	626,976	658,623
Segment profit	54,675	46,196	172,707	151,583
Selling, general and administrative expenses (exclusive of depreciation and amortization)	35,367	44,369	111,774	137,604
Depreciation and amortization	14,398	17,737	45,848	53,942
Impairment of goodwill and other intangible assets		29,565		29,565
Related party expense	2,845	2,016	8,696	6,189
Interest expense, net	24,708	40,897	113,980	122,928
Debt modification and extinguishment costs (gain), net	(571)	(4,696)	(16,129)	4,305
Sundry expense, net	298	781	2,546	347
Other expense (income), net	(1,069)	(1,115)	(1,583)	12,419
Net loss before income taxes	(21,301)	(83,358)	(92,425)	(215,716)
I T P S Segment
Segment information
Revenue	172,150	185,309	550,848	580,320
Cost of revenue (exclusive of depreciation and amortization)	141,808	157,269	450,353	477,559
Segment profit	30,342	28,040	100,495	102,761
H S Segment
Segment information
Revenue	62,090	60,955	188,740	173,940
Cost of revenue (exclusive of depreciation and amortization)	45,430	48,316	139,182	140,767
Segment profit	16,660	12,639	49,558	33,173
L L P S Segment
Segment information
Revenue	18,885	17,774	60,095	55,946
Cost of revenue (exclusive of depreciation and amortization)	11,212	12,257	37,441	40,297
Segment profit	$ 7,673	$ 5,517	$ 22,654	$ 15,649