Time charter revenue, Operating revenue (Table) (Details) - Sales Revenue, Net [Member]	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
CMA CGM [Member]
Percentage of revenue	80.41%	77.82%	77.29%
OOCL [Member]
Percentage of revenue		22.18%	22.71%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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