Annual report pursuant to Section 13 and 15(d)

Operating Segments - Summarized Segment Financial Information (Parenthetical) (Details)

v3.21.1
Operating Segments - Summarized Segment Financial Information (Parenthetical) (Details)
$ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Dec. 31, 2020
USD ($)
Vechicle
Dec. 31, 2019
USD ($)
Vechicle
Dec. 31, 2018
USD ($)
Segment Reporting Information [Line Items]          
Asset impairments     $ 3,310 $ 17,223 $ 4,445
Gain on sale of South Texas Properties, net         7,700
Gain on insurance recoveries         3,571
Contract assets $ 67,521 $ 52,128 67,521 52,128  
Contract receivables 15,129 26,271 $ 15,129 26,271  
Forty-Vehicle Ferry          
Segment Reporting Information [Line Items]          
Increase in operating income (loss) due to project charges       5,100  
Revenue reclassified between the Shipyard and Fabrication & Services segments       $ 9,200  
Number of vehicle ferry projects | Vechicle     2 2  
Contract assets   6,000   $ 6,000  
Contract receivables   6,000   6,000  
Corporate          
Segment Reporting Information [Line Items]          
Restructuring costs       700  
Shipyard          
Segment Reporting Information [Line Items]          
Increase in operating income (loss) due to project charges $ 8,800 10,200 $ 16,600 12,300 6,700
Asset impairments     1,600 7,900 1,000
Charges associated with damage caused by Hurricane Laura     1,300    
F&S          
Segment Reporting Information [Line Items]          
Increase in operating income (loss) due to project charges   $ 3,800 2,700 4,900 2,400
Asset impairments     2,500 $ 8,900 7,800
Gain on settlement of contract dispute     $ 10,000    
Shipyard, Fabrication and Services          
Segment Reporting Information [Line Items]          
Asset impairments         $ 3,500