Revenue, Contract Assets and Liabilities and Other Contract Matters - Summary of Remaining Performance Obligation by Operating Segment (Details) $ in Thousands	Mar. 31, 2021 USD ($)
Operating Segments
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 339,628
Fabrication & Services | Operating Segments
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	12,273
Shipyard
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	2,900
Shipyard | Operating Segments
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 327,355