Acquisition (Narrative) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2014 Barges Boats	Jul. 22, 2013 Barges Tug_Boats
Business Acquisition [Line Items]
Business Acquisition, Transaction Costs		$ 230.9
Business Acquisition, Barges Acquired		9
Business Acquisition, Tug Boats Acquired		9
NumberOfBarges	60
NumberOfBoats	23
Property, Plant and Equipment, Estimated Useful Lives	25

Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-URI http://asc.fasb.org/subtopic&trid=2155824

Name:	us-gaap_PropertyPlantAndEquipmentEstimatedUsefulLives
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration