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Nature of Operations and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2014
Mar. 31, 2017
Mar. 31, 2016
Mar. 31, 2015
Property, Plant and Equipment [Line Items]        
Extended useful life, months   30 months    
Inspection interval   The majority of the company’s vessels require certification inspections twice in every five year period    
Goodwill impairment $ 283,700     $ 283,699
Stacked Vessels        
Property, Plant and Equipment [Line Items]        
Property plant and equipment average age   11 years 6 months 12 years 6 months  
Maximum        
Property, Plant and Equipment [Line Items]        
Highly liquid investments, maturities   3 months    
Maximum | Marine Equipment        
Property, Plant and Equipment [Line Items]        
Percentage of salvage values   10.00%    
Maximum | Marine Equipment | From Date of Construction        
Property, Plant and Equipment [Line Items]        
Estimated useful lives, years   25 years    
Maximum | Other Property Plant and Equipment        
Property, Plant and Equipment [Line Items]        
Estimated useful lives, years   30 years    
Minimum | Marine Equipment        
Property, Plant and Equipment [Line Items]        
Percentage of salvage values   5.00%    
Minimum | Marine Equipment | From Date of Construction        
Property, Plant and Equipment [Line Items]        
Estimated useful lives, years   15 years    
Minimum | Marine Equipment | Regardless of Date Constructed        
Property, Plant and Equipment [Line Items]        
Estimated useful lives, years   6 years    
Minimum | Other Property Plant and Equipment        
Property, Plant and Equipment [Line Items]        
Estimated useful lives, years   3 years