Revenue, Contract Assets and Liabilities and Other Contract Matters - Summary of Remaining Performance Obligation by Operating Segment (Details) - Operating Segments $ in Thousands	Jun. 30, 2021 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 23,914
Fabrication & Services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	9,326
Shipyard
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 14,588