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VESSELS, NET (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
VESSELS, NET [Abstract] |  |  |
Total number of vessels | 20 | 17 | 15
Number of vessels the fleet has increased over prior year | 3 |  |
Number of vessels categorized as newbuildings |  | 2 |
Schedule of Vessels [Line Items] |  |  |
Carrying Value | $ 1,022,793 | $ 988,263 |
Accumulated depreciation | 344,244 | 295,526 |
Depreciation expense | 64,626 | 62,545 | 55,035
Capitalized Costs of Newbuildings [Abstract] |  |  |
Total Newbuilding | 134,544 | 72,125 |
Vessels [Member] |  |  |
Schedule of Vessels [Line Items] |  |  |
Carrying Value | 1,005,147 | 971,018 |
Accumulated depreciation | 334,846 | 275,744 |
Depreciation expense | 59,102 | 53,181 |
Drydocking [Member] |  |  |
Schedule of Vessels [Line Items] |  |  |
Carrying Value | 17,646 | 17,245 |
Accumulated depreciation | 9,398 | 19,782 |
Depreciation expense | 5,524 | 9,364 |
Nordic Breeze [Member] |  |  |
Schedule of Vessels [Line Items] |  |  |
Percentage of purchase price payable upon signing of contract (in hundredths) | 55.00% |  |
Capitalized Costs of Newbuildings [Abstract] |  |  |
Installment | 64,750 | 35,700 |
Capitalized interest | 417 | 191 |
Capitalized cost | 2,091 | 183 |
Total Newbuilding | 67,258 | 36,074 |
Nordic Zenith [Member] |  |  |
Schedule of Vessels [Line Items] |  |  |
Percentage of purchase price payable upon signing of contract (in hundredths) | 55.00% |  |
Capitalized Costs of Newbuildings [Abstract] |  |  |
Installment | 64,750 | 35,700 |
Capitalized interest | 501 | 191 |
Capitalized cost | 2,035 | 160 |
Total Newbuilding | $ 67,286 | $ 36,051 |

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