Assets Held For Sale (Narrative) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) item	Mar. 31, 2015 USD ($) item
Property, Plant and Equipment [Line Items]
Proceeds from sale of assets	$ 5,093	$ 2,861
Related debt paid off		$ 13,500
Oslo Bulk AS [Member]
Property, Plant and Equipment [Line Items]
Percentage of ownership interest exchanged	25.00%
Oslo Bulk Holding Pte. Ltd. [Member]
Property, Plant and Equipment [Line Items]
Percentage of ownership interest exchanged	23.68%
Saltholmen Shipping Ltd. [Member]
Property, Plant and Equipment [Line Items]
Percentage ownership investment sold	30.00%
Proceeds from sale of percentage of ownership interest	$ 5,700
Brattholmen Shipping Ltd. [Member]
Property, Plant and Equipment [Line Items]
Percentage ownership investment sold	30.00%
Proceeds from sale of percentage of ownership interest	$ 1,500
Handysize Vessel [Member]
Property, Plant and Equipment [Line Items]
Number of vessels sold \| item	2	1
Related debt paid off		$ 13,500
Capesize Bulk Carrier [Member]
Property, Plant and Equipment [Line Items]
Number of vessels sold \| item	2
Chemical Tankers [Member]
Property, Plant and Equipment [Line Items]
Number of vessels owned or operated \| item	2
Percentage ownership investment sold	30.00%
Asphalt Tankers [Member]
Property, Plant and Equipment [Line Items]
Number of vessels owned or operated \| item	2
Percentage ownership investment sold	30.00%
Dry Bulk Carriers [Member] \| Handysize Vessel [Member]
Property, Plant and Equipment [Line Items]
Number of vessels sold \| item	2
Proceeds from sale of assets	$ 20,700
Related debt paid off	25,100
Decrease in debt outstanding	1,500
Dry Bulk Carriers [Member] \| Capesize Bulk Carrier [Member]
Property, Plant and Equipment [Line Items]
Proceeds from sale of assets	10,100
Related debt paid off	$ 8,600
Dry Bulk Carriers [Member] \| Mini-Bulk Carrier [Member]
Property, Plant and Equipment [Line Items]
Number of vessels owned or operated \| item	15

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

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Number of vessels sold

+ References

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- Definition

Ownership Investment Sold Percentage

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- Definition

Percentage Of Ownership Interest Exchanged

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- Definition

Net increase or decrease in the carrying amount of the debt instrument for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph f
-Article 4

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The cash inflow associated with the sale of 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.

+ 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 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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