Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Revenues	$ 427,216	$ 536,668	$ 495,781	$ 963,884	$ 989,667
Remotely Operated Vehicles [Member]
Segment Reporting Information [Line Items]
Revenues	98,778	111,780	120,363	210,558	220,709
Subsea Products [Member]
Segment Reporting Information [Line Items]
Revenues	130,655	194,838	138,910	325,493	267,754
Subsea Projects [Member]
Segment Reporting Information [Line Items]
Revenues	56,326	61,455	75,104	117,781	164,832
Asset Integrity [Member]
Segment Reporting Information [Line Items]
Revenues	48,077	59,132	61,156	107,209	121,845
Oil and Gas [Member]
Segment Reporting Information [Line Items]
Revenues	333,836	427,205	395,533	761,041	775,140
Advanced Technologies [Member]
Segment Reporting Information [Line Items]
Revenues	$ 93,380	$ 109,463	$ 100,248	$ 202,843	$ 214,527