Quarterly report pursuant to Section 13 or 15(d)

Note 15 - Segment Information (Details Textual)

v3.10.0.1
Note 15 - Segment Information (Details Textual) - USD ($)
$ in Thousands
Sep. 30, 2018
Dec. 31, 2017
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Total $ 120,340 $ 92,169
MexMar [Member]    
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Total 63,800  
Other Offshore Marine Services Joint Ventures [Member]    
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Total $ 56,500