Amount Billed For Building Incentive

No definition available.

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- Definition

Amount Spent On Construction Of Building

+ References

No definition available.

+ Details

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- Definition

Incentive Received For Construction Of Office Building

+ References

No definition available.

+ Details

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- Definition

Proceeds From Incentive

+ References

No definition available.

+ Details

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- Definition

Gross amount of long-lived physical assets excluding from construction in progress of vessel and non vessel.

+ References

No definition available.

+ Details

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- Definition

Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets excluding from capital in progress of vessel and non vessel.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.14)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 14

-Article 5

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

+ Details

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 13

-Subparagraph a

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 7

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Property, Plant And Equipment (Details) (USD $)	12 Months Ended
Property, Plant And Equipment (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property plant and equipment gross excluding construction in progress of vessel and non vessel	$ 558,812,000	$ 622,325,000
Less: Accumulated depreciation	(186,450,000)	(175,106,000)
Property plant and equipment net excluding construction in progress vessel and non vessel	372,362,000	447,219,000
Construction-in-progress (vessel and non-vessel)	2,371,000us-gaap_ConstructionInProgressGross	2,673,000us-gaap_ConstructionInProgressGross
Net Vessels, Property, Plant and Equipment	374,733,000us-gaap_PropertyPlantAndEquipmentNet	449,892,000us-gaap_PropertyPlantAndEquipmentNet
Depreciation expense	26,984,000us-gaap_Depreciation	24,930,000us-gaap_Depreciation	24,975,000us-gaap_Depreciation
Incentive received from the State of Louisiana for the construction of office building	5,200,000
Amount spent on the construction of building	4,800,000ish_AmountSpentOnConstructionOfBuilding
Amount billed to the State of Louisiana toward the building incentive	4,700,000ish_AmountBilledForBuildingIncentive
Amount received from the State of Louisiana	4,579,000ish_ProceedsFromIncentive
PCTC [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross excluding construction in progress of vessel and non vessel	190,469,000	146,190,000
Special Purpose Vessels [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross excluding construction in progress of vessel and non vessel	59,481,000	59,481,000
Coal Carrier [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross excluding construction in progress of vessel and non vessel	92,771,000	92,771,000
Tanker [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross excluding construction in progress of vessel and non vessel		8,009,000
Bulk Carriers [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross excluding construction in progress of vessel and non vessel	118,732,000	203,394,000
Tug And Barge Units [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross excluding construction in progress of vessel and non vessel	58,573,000	72,571,000
Non-Vessel Related Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross excluding construction in progress of vessel and non vessel	38,786,000	39,909,000
Property, Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 27,000,000	$ 24,900,000	$ 25,000,000