Prepaid Expenses and Other Current Assets (Table) (Details) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
PREPAID EXPENSES AND OTHER CURRENT ASSETS [Abstract]    
Prepaid voyage and operating costs $ 9,261 $ 8,022
Claims receivable 22,224 12,307
Prepaid other taxes 2,682 4,520
Advances for working capital purposes 18 18
Other 6,005 2,516
Total prepaid expenses and other current assets $ 40,190 $ 27,383