Business Segment Information - Summary Of Financial Data By Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting Information [Line Items]
Net revenues	$ 150,329	$ 107,267	$ 254,857	$ 198,306
Income (loss) from operations	5,050	(9,295)	(12,655)	(40,051)
Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Net revenues	(11,018)	(10,523)	(19,454)	(16,016)
Income (loss) from operations	221	163	442	331
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Income (loss) from operations	(8,701)	(9,827)	(18,663)	(18,496)
Well Intervention [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net revenues	113,076	59,919	187,697	105,975
Income (loss) from operations	19,032	(538)	20,450	(17,226)
Well Intervention [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Net revenues	(2,895)	(2,201)	(4,268)	(2,842)
Robotics [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net revenues	33,061	38,914	55,029	70,908
Income (loss) from operations	(11,642)	(8,823)	(27,948)	(21,573)
Robotics [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Net revenues	(8,123)	(8,322)	(15,186)	(13,174)
Production Facilities [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net revenues	15,210	18,957	31,585	37,439
Income (loss) from operations	$ 6,140	$ 9,730	$ 13,064	$ 16,913