Amount of deferred gain on the purchase of property recognized during the period.

No definition available.

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- Definition

The number of pure car truck carriers sold during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	ish_
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- Definition

Represents the number of vessel sold during period.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

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

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- Definition

Amount of gain (loss) on sale or disposal of other assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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

+ Details

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Balance Type:	credit
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- Definition

The net cash outflow or inflow from purchases, sales and disposals of property, plant and equipment and other productive assets, including intangibles.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

+ Details

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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- Details

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Gain On Sale Of Other Assets (Details) (USD $)	1 Months Ended		12 Months Ended			3 Months Ended
Gain On Sale Of Other Assets (Details) (USD $)	Oct. 22, 2012	Mar. 31, 2012 item	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2012 item
Property, Plant and Equipment [Line Items]
Number of International Flag Pure Car Truck Carriers sold		2ish_NumberOfPureCarTruckCarriersSold
Proceeds from sale of other assets		$ 73,900,000
Gain on sale of other assets		3,800,000us-gaap_GainLossOnSaleOfOtherAssets	(2,000)us-gaap_GainLossOnSaleOfOtherAssets	(16,000)us-gaap_GainLossOnSaleOfOtherAssets	16,625,000us-gaap_GainLossOnSaleOfOtherAssets
Repayments of debt from sale proceeds		36,100,000us-gaap_RepaymentsOfLongTermDebt
Payments to acquire vessel	3,700,000
Gain recognized from exchange transactions					12,200,000us-gaap_GainLossOnDispositionOfAssets
US Flag PCTC Vessel [Member]
Property, Plant and Equipment [Line Items]
Deferred gain on purchase of property						239,000
Number of vessel sold						1
Molten Sulphur Carrier [Member]
Property, Plant and Equipment [Line Items]
Deferred gain on purchase of property						$ 430,000
Number of vessel sold						1