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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 4)	12 Months Ended
	Dec. 31, 2012 item	Dec. 31, 2011 item	Dec. 31, 2010 item
Concentration of credit risk
Percentage of revenue earned	100.00%	100.00%	100.00%
Number of customers	43	32	33
Number of financial institutions with which the entity maintains its cash and cash equivalents	4	5
Number of interest swap agreements	5	8
Voyage Revenues
Concentration of credit risk
Number of customers that individually accounted for more than 10% of voyage revenues	1	2	2
Voyage Revenues | Cargill International S.A.
Concentration of credit risk
Concentration risk percentage	31.27%	30.00%	29.26%
Voyage Revenues | Swissmarine Services S.A.
Concentration of credit risk
Concentration risk percentage		12.23%
Voyage Revenues | Pacific Basin Chartering Ltd.
Concentration of credit risk
Concentration risk percentage			11.43%

X

- Definition

Represents the number customers of the entity from which revenue was earned.

+ References

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Represents the number of financial institutions with which the entity maintains its cash and cash equivalents.

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- Definition

Percentage of revenue earned from customers.

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- Definition

Represents the number of external customers from which the entity generated 10 percent or more of revenues.

+ References

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- Definition

Percentage of revenue generated from a single external customer that accounts for 10 percent or more of an entity's revenues.

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

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