Business Segment Information - Summary Of Financial Data By Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Net revenues	$ 164,262	$ 104,528
Income (loss) from operations	(1,116)	(17,705)
Intercompany Elimination
Segment Reporting Information [Line Items]
Net revenues	(8,797)	(8,436)
Income (loss) from operations	221	221
Corporate and Other
Segment Reporting Information [Line Items]
Income (loss) from operations	(8,256)	(9,962)
Well Intervention | Reportable Segments
Segment Reporting Information [Line Items]
Net revenues	129,569	74,621
Income (loss) from operations	13,877	1,418
Well Intervention | Intercompany Elimination
Segment Reporting Information [Line Items]
Net revenues	(1,952)	(1,373)
Robotics | Reportable Segments
Segment Reporting Information [Line Items]
Net revenues	27,169	21,968
Income (loss) from operations	(14,317)	(16,306)
Robotics | Intercompany Elimination
Segment Reporting Information [Line Items]
Net revenues	(6,845)	(7,063)
Production Facilities | Reportable Segments
Segment Reporting Information [Line Items]
Net revenues	16,321	16,375
Income (loss) from operations	$ 7,359	$ 6,924