Revenue, Contract Assets and Liabilities and Other Contract Matters - Summary of Remaining Performance Obligation by Operating Segment (Details) $ in Thousands	Jun. 30, 2020 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 448,104
Operating Segments
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	448,104
Fabrication & Services | Operating Segments
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	30,547
Shipyard | Operating Segments
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 417,557