Revenue From Contracts With Customers - Disaggregation Of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Net revenues	$ 181,021	$ 166,823
Intercompany Eliminations
Disaggregation of Revenue [Line Items]
Net revenues	(10,430)	(9,702)
Well Intervention
Disaggregation of Revenue [Line Items]
Net revenues	140,652	122,231
Well Intervention | Intercompany Eliminations
Disaggregation of Revenue [Line Items]
Net revenues	(3,304)	(3,225)
Robotics
Disaggregation of Revenue [Line Items]
Net revenues	35,258	39,041
Robotics | Intercompany Eliminations
Disaggregation of Revenue [Line Items]
Net revenues	(7,126)	(6,477)
Production Facilities
Disaggregation of Revenue [Line Items]
Net revenues	15,541	15,253
Short-term
Disaggregation of Revenue [Line Items]
Net revenues	104,765	54,735
Short-term | Intercompany Eliminations
Disaggregation of Revenue [Line Items]
Net revenues	0	0
Short-term | Well Intervention
Disaggregation of Revenue [Line Items]
Net revenues	82,324	29,805
Short-term | Robotics
Disaggregation of Revenue [Line Items]
Net revenues	22,441	24,930
Short-term | Production Facilities
Disaggregation of Revenue [Line Items]
Net revenues	0	0
Long-term
Disaggregation of Revenue [Line Items]
Net revenues	76,256	112,088
Long-term | Intercompany Eliminations
Disaggregation of Revenue [Line Items]
Net revenues	(10,430)	(9,702)
Long-term | Well Intervention
Disaggregation of Revenue [Line Items]
Net revenues	58,328	92,426
Long-term | Robotics
Disaggregation of Revenue [Line Items]
Net revenues	12,817	14,111
Long-term | Production Facilities
Disaggregation of Revenue [Line Items]
Net revenues	$ 15,541	$ 15,253