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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, Concentration of credit risk (Details) | 12 Months Ended
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Dec. 31, 2013 Customer Derivative Institution | Dec. 31, 2012 Customer Institution Derivative | Dec. 31, 2011 Customer
Concentration Risk [Line Items] |  |  |
Percentage of revenue earned (in hundredths) | 100.00% | 100.00% | 100.00%
Number of customers | 48 | 43 | 32
Number of financial institutions with which the entity maintains its cash and cash equivalents | 4 | 4 |
Number of interest swap agreements | 4 | 5 |
Voyage Revenues [Member] |  |  |
Concentration Risk [Line Items] |  |  |
Major Customers | 3 | 1 | 2
Concentration risk percentage (in hundredths) | 10.00% | 10.00% | 10.00%
Voyage Revenues [Member] | Cargill International S.A. [Member] |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk percentage (in hundredths) | 21.45% | 31.27% | 30.00%
Voyage Revenues [Member] | Swissmarine Services S.A. [Member] |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk percentage (in hundredths) | 18.73% |  | 12.23%
Voyage Revenues [Member] | Pacific Basin Chartering Ltd [Member] |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk percentage (in hundredths) | 10.30% |  |

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- Definition Represents the number of financial institutions with which the entity maintains its cash and cash equivalents. + References No definition available. + Details
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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) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13537-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13531-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592 + Details
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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 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 Reference 2: 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 + Details
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