Annual report pursuant to Section 13 and 15(d)

Business Segments and Customer Information (Narrative) (Details)

v3.6.0.2
Business Segments and Customer Information (Narrative) (Details)
$ in Millions
12 Months Ended
Dec. 31, 2016
USD ($)
Segment
Segment Reporting Information [Line Items]  
Number of reportable operating segments | Segment 4
Corporate  
Segment Reporting Information [Line Items]  
Gain resulting from the combined effect of the Anchorage Lawsuit and Maritime Administration settlements $ 1.4
Corporate | Heritage Litigation  
Segment Reporting Information [Line Items]  
Settlement amount $ 3.3