Segment Information (Table) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenue	$ 211,652	$ 190,524	$ 223,676
Asia
Revenue	125,618	112,019	133,542
Europe
Revenue	47,308	54,006	70,121
North America
Revenue	20,307	13,364	10,557
Australia
Revenue	$ 18,419	$ 11,135	$ 9,456

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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