Business Acquisition Percentage Of Voting Interests Acquired Two

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- Definition

Number Of Carriers With Shareholding Interest Held

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No definition available.

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- Definition

Number Of Carriers With Shareholding Interest Held

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No definition available.

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- Definition

Refers to the number of pure car truck carriers owned out of seven PCTC's.

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No definition available.

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- Definition

Refers to the number of pure car truck carriers with buy back options in future.

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Refers to the number of units.

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No definition available.

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- Definition

Number Of Units Chartered To One Customer

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No definition available.

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- Definition

Number Of Vessels Employed On Long-Term Bareboat Charters

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No definition available.

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- Definition

Number Of Vessels Held For Sale

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No definition available.

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- Definition

Number Of Vessels On Time Charter To Another Company

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No definition available.

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- Definition

Number of vessels owned or operated by the entity as of balance sheet date.

+ References

No definition available.

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- Definition

Number Of Vessels Redelivered

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No definition available.

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- Definition

Number of vessels sold

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No definition available.

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- Definition

Refers to the number of vessels which deploy in this segment.

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No definition available.

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- Definition

Percentage of the entity's total work force that is covered by these agreements.

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No definition available.

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- Definition

Refers to the weight of diversified bulk carrier.

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No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

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-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

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-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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- Definition

The number of businesses acquired by the entity during the period.

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No definition available.

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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Significant Operations (Narrative) (Details) (USD $)	1 Months Ended	3 Months Ended								12 Months Ended			0 Months Ended	2 Months Ended	1 Months Ended
Significant Operations (Narrative) (Details) (USD $)	Aug. 31, 2012 item	Dec. 31, 2014 item	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014 item	Dec. 31, 2013	Dec. 31, 2012	Mar. 05, 2015 item	Mar. 05, 2015 item	Oct. 31, 2013	Jul. 31, 2013	Dec. 31, 2006 item	Nov. 30, 2013
Segment Reporting Information [Line Items]
Total Revenues		$ 70,978,000us-gaap_Revenues	$ 74,410,000us-gaap_Revenues	$ 76,752,000us-gaap_Revenues	$ 72,694,000us-gaap_Revenues	$ 76,169,000us-gaap_Revenues	$ 77,938,000us-gaap_Revenues	$ 74,897,000us-gaap_Revenues	$ 81,124,000us-gaap_Revenues	$ 294,834,000us-gaap_Revenues	$ 310,128,000us-gaap_Revenues	$ 243,496,000us-gaap_Revenues
Number of vessels owned or operated																	2ish_NumberOfVesselsOwnedOrOperated
Number of vessels held for sale		5ish_NumberOfVesselsHeldForSale
Percentage of total work force that is covered by collective bargaining agreements (in hundredths)										75.00%
Percentage of shareholders interest owned																23.68%
Number of Businesses Acquired	2us-gaap_NumberOfBusinessesAcquired
Payment for investment in Unconsolidated Entities										7,887,000	3,520,000	1,000,000
Number of vessels immediately employed on long-term bareboat charters										4
MSP [Member]
Segment Reporting Information [Line Items]
Number of units										8
United States [Member]
Segment Reporting Information [Line Items]
Total Revenues										165,268,000	192,332,000	123,782,000
Asian Countries [Member]
Segment Reporting Information [Line Items]
Total Revenues										62,542,000	67,830,000	63,860,000
Rail-Ferry Service [Member]
Segment Reporting Information [Line Items]
Total Revenues										32,521,000	34,366,000	32,479,000
South America [Member]
Segment Reporting Information [Line Items]
Total Revenues											2,905,000	10,416,000
Other Countries [Member]
Segment Reporting Information [Line Items]
Total Revenues										24,054,000	5,729,000	485,000
Europe [Member]
Segment Reporting Information [Line Items]
Total Revenues										10,449,000	6,966,000	12,474,000
PCTC [Member]
Segment Reporting Information [Line Items]
Number of units										7
PCTC [Member] \| Time Charter Contracts - U.S. Flag [Member]
Segment Reporting Information [Line Items]
Number of units chartered to one customer										6
Number of Pure Car Truck Carriers owned										2
Number of Pure Car Truck Carriers with Buy Back Options										2
Special Purpose Vessels [Member]
Segment Reporting Information [Line Items]
Number of vessels owned or operated		2								2
Dry Bulk Carriers [Member]
Segment Reporting Information [Line Items]
Number of units										5
Number of vessels owned or operated		7								7
Number of vessels redelivered										2
Mini-Bulk Carrier [Member]
Segment Reporting Information [Line Items]
Weight of diversified bulk carrier (in whole number)										8,000
Capesize Bulk Carrier [Member]
Segment Reporting Information [Line Items]
Weight of diversified bulk carrier (in whole number)										170,578
Handysize Bulk Carriers [Member]
Segment Reporting Information [Line Items]
Number of vessels held for sale		3								3
Handysize Bulk Carriers [Member] \| Subsequent Event [Member]
Segment Reporting Information [Line Items]
Number of vessels sold													1
Number of vessels held for sale														2
Integrated Barge And Tug Unit [Member]
Segment Reporting Information [Line Items]
Number of vessels owned or operated		1								1
Rail-Ferry Service [Member] \| Terminales Transgolfo, S.A. de C.V. [Member]
Segment Reporting Information [Line Items]
Percentage of shareholders interest owned		49.00%								49.00%
Rail-Ferry Service [Member] \| Roll On/Roll Off vessels [Member]
Segment Reporting Information [Line Items]
Number of units										2
Rail-Ferry Service [Member] \| Special Purpose Vessels [Member]
Segment Reporting Information [Line Items]
Total Revenues										34,600,000	37,200,000	33,300,000
Jones Act [Member] \| TEC And Mosaic [Member]
Segment Reporting Information [Line Items]
Number of units										6
Concentration risk percentage										62.00%	53.00%	58.00%
Jones Act [Member] \| Bulk Carriers [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										2
Jones Act [Member] \| Integrated Barge And Tug Unit [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										3
Jones Act [Member] \| Tug [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										1
Jones Act [Member] \| Barge [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										1
Jones Act [Member] \| Harbor Tug [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										1
Jones Act [Member] \| Belt Self-Unloading Coal Carrier [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										1
Jones Act [Member] \| Molten Sulphur Carrier Vessel [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										1
PCTC [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										7
PCTC [Member] \| Time Charter Contracts - U.S. Flag [Member]
Segment Reporting Information [Line Items]
Total Revenues										37,900,000	36,500,000	37,400,000
PCTC [Member] \| MSP [Member]
Segment Reporting Information [Line Items]
Total Revenues										24,500,000	22,300,000	24,100,000
PCTC [Member] \| United States [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										4
PCTC [Member] \| International [Member]
Segment Reporting Information [Line Items]
Number of vessels which deployed										3
PCTC [Member] \| Supplemental Cargo [Member]
Segment Reporting Information [Line Items]
Total Revenues										16,100,000	30,800,000	44,700,000
Dry Bulk Carriers [Member]
Segment Reporting Information [Line Items]
Total Revenues										18,000,000	21,100,000	26,100,000
Bulk Carriers [Member] \| Mini-Bulk Carrier [Member]
Segment Reporting Information [Line Items]
Percentage of shareholders interest owned		25.00%				25.00%				25.00%	25.00%					23.68%
Percentage of shareholders interest owned on the other 8 carriers		23.68%								23.68%
Number of carriers with 25% shareholding interest held										8
Number of carriers with 23.68% shareholding interest held										8
Specialty Contracts [Member] \| MSP [Member]
Segment Reporting Information [Line Items]
Total Revenues										24,500,000	22,300,000	24,100,000
Specialty Contracts [Member] \| Container Vessels [Member]
Segment Reporting Information [Line Items]
Number of vessels on time charter to another company		2								2
Number of vessels owned or operated		3								3
Specialty Contracts [Member] \| Multi-Purpose Vessels [Member]
Segment Reporting Information [Line Items]
Number of vessels owned or operated		2								2
Specialty Contracts [Member] \| Tankers [Member]
Segment Reporting Information [Line Items]
Number of vessels owned or operated		6								6
Specialty Contracts [Member] \| Multi-Purpose Heavy Lift Vessel [Member]
Segment Reporting Information [Line Items]
Number of vessels owned or operated		1								1
Specialty Contracts [Member] \| Multi-Purpose Ice Strengthened [Member]
Segment Reporting Information [Line Items]
Number of vessels owned or operated		1								1
Saltholmen Shipping Ltd. [Member]
Segment Reporting Information [Line Items]
Equity investee ownership interest		30.00%								30.00%								30.00%
Payment for investment in Unconsolidated Entities					5,800,000					5,800,000					2,700,000
Saltholmen Shipping Ltd. [Member] \| Chemical Tankers [Member]
Segment Reporting Information [Line Items]
Number of vessels owned or operated		2								2
Brattholmen Shipping Ltd. [Member]
Segment Reporting Information [Line Items]
Equity investee ownership interest		30.00%								30.00%
Payment for investment in Unconsolidated Entities										$ 2,100,000
Brattholmen Shipping Ltd. [Member] \| Asphalt Tankers [Member]
Segment Reporting Information [Line Items]
Number of vessels owned or operated		2								2