Acquisition (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014 Barges Boats	Jul. 22, 2013 Barges Tug_Boats
Business Acquisition [Line Items]
Business Acquisition, Transaction Costs		$ 230,900,000
Business Acquisition, Barges Acquired		9
Business Acquisition, Tug Boats Acquired		9
NumberOfBarges	54
NumberOfBoats	23
Property, Plant and Equipment, Estimated Useful Lives	25
Amended Facility [Member]
Business Acquisition [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,000,000,000