Annual report pursuant to Section 13 and 15(d)

Organization and Summary of Significant Accounting Policies (Details)

v3.6.0.2
Organization and Summary of Significant Accounting Policies (Details)
$ in Millions
12 Months Ended
Dec. 31, 2016
USD ($)
vessel
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Significant Accounting Policies [Line Items]      
Unapproved change order and claim revenue | $ $ 0.0 $ 0.0 $ 0.0
Workers compensation liability | $ $ 3.4 $ 2.6  
Number of technologically advanced offshore support vessels being constructed | vessel 2    
Number of multi-purpose service vessels being constructed | vessel 2    
Minimum      
Significant Accounting Policies [Line Items]      
Estimated useful life of property, plant and equipment 3 years    
Maximum      
Significant Accounting Policies [Line Items]      
Estimated useful life of property, plant and equipment 25 years