Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurement (Details)

v3.8.0.1
Fair Value Measurement (Details) - Disposal Group, Held-for-sale, Not Discontinued Operations - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Dec. 31, 2017
Mar. 31, 2017
Shipyard Division Assets      
Long Lived Assets Held-for-sale [Line Items]      
Impairment of assets held for sale   $ 600 $ 389
Texas North Yard      
Long Lived Assets Held-for-sale [Line Items]      
Impairment of real estate $ 5,100