Impairment Loss (Details) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($) item	Dec. 31, 2014 USD ($) item	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)
Property, Plant and Equipment [Line Items]
Goodwill impairment loss					$ 1,907
Short term assets held for sale	$ 5,300		$ 6,976		5,300
Impairment of Long-Lived Assets held for sale					1,135
Fair value of asset held for sell	5,300				5,300
Jones Act [Member]
Property, Plant and Equipment [Line Items]
Goodwill impairment loss					1,900
Fair value of asset held for sell	5,300				5,300
Jones Act Tug-Barge [Member]
Property, Plant and Equipment [Line Items]
Number of vessels held for sale | item			1
Impairment of Long-Lived Assets held for sale	1,100				1,100
Tug-Barge Unit [Member] | Jones Act [Member]
Property, Plant and Equipment [Line Items]
Short term assets held for sale	$ 6,400				$ 6,400
Handysize Vessel [Member]
Property, Plant and Equipment [Line Items]
Number of vessels held for sale | item		2	3
Impairment of Long-Lived Assets held for sale		$ 1,800		$ 1,800