Segment Information (Table) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue	$ 50,018	$ 44,877	$ 92,429	$ 90,518
Asia
Revenue	30,250	29,289	55,047	56,520
Europe
Revenue	10,217	9,561	19,683	22,588
North America
Revenue	5,161	3,173	9,654	5,769
Australia
Revenue	$ 4,390	$ 2,854	$ 8,045	$ 5,641

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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