Business Segment Information - Summary Of Financial Data By Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Net revenues	$ 163,260	$ 161,245	$ 418,117	$ 359,551
Income (loss) from operations	4,767	21,470	(7,888)	(18,581)
Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Net revenues	(11,691)	(13,067)	(31,145)	(29,083)
Income (loss) from operations	199	(873)	641	(542)
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Income (loss) from operations	(10,633)	(10,288)	(29,296)	(28,784)
Well Intervention [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net revenues	111,522	108,287	299,219	214,262
Income (loss) from operations	16,906	24,413	37,356	7,187
Well Intervention [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Net revenues	(3,765)	(2,898)	(8,033)	(5,740)
Robotics [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net revenues	47,049	48,897	102,078	119,805
Income (loss) from operations	(9,365)	(94)	(37,313)	(21,667)
Robotics [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Net revenues	(7,926)	(10,169)	(23,112)	(23,343)
Production Facilities [Member] | Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net revenues	16,380	17,128	47,965	54,567
Income (loss) from operations	$ 7,660	$ 8,312	$ 20,724	$ 25,225