Assets Held For Sale (Details) (USD $)	3 Months Ended
Mar. 31, 2015 item	Dec. 31, 2014 item
Property, Plant and Equipment [Line Items]
Long Term Assets Held for Sale	$ 32,486,000	$ 48,701,000
Short Term Assets Held for Sale	6,778,000	6,976,000
Handysize Vessel [Member]
Property, Plant and Equipment [Line Items]
Number of vessels held for sale		3
Long Term Assets Held for Sale	32,500,000	48,700,000
Number of vessels sold	1
Debt incurred to purchase vessels	27,000,000
Jones Act Tug-Barge [Member]
Property, Plant and Equipment [Line Items]
Number of vessels held for sale		1
Tug-Barge Unit And Inventory Related To Handysize Vessels [Member]
Property, Plant and Equipment [Line Items]
Short Term Assets Held for Sale	6,800,000	7,000,000
Depreciation expense	$ 0

Disposal Group Including Discontinued Operation Debt Incurred

No definition available.

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- Definition

Number Of Vessels Held For Sale

+ References

No definition available.

+ Details

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- Definition

Number of vessels sold

+ References

No definition available.

+ Details

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- Definition

The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for current assets (assets with expected useful life shorter than one year or one operating cycle, whichever is longer) of a disposal group, including a component of the entity (discontinued operation), to be sold or that has subsequently been disposed of through sale, as of the financial statement date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

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- Definition

The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for noncurrent assets (assets with expected useful life longer than one year or one operating cycle, whichever is longer) of a disposal group, including a component of the entity (discontinued operation), to be sold or that has subsequently been disposed of through sale, as of the financial statement date.

+ References

+ Details

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- Definition

Amount of depreciation and amortization attributable to disposal group.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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