PREPAID EXPENSES AND OTHER CURRENT AND NONCURRENT ASSETS (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
PREPAID EXPENSES AND OTHER CURRENT AND NONCURRENT ASSETS
Lubricant inventory, fuel oil and diesel oil inventory and other stores	$ 12,043	$ 10,322
Prepaid items	5,842	5,067
Insurance receivable	1,500	1,817
Other	1,662	940
Total prepaid expenses and other current assets	21,047	18,146
Security deposit related to operating lease included in other noncurrent assets	$ 514	$ 514

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Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment after one year or beyond the operating cycle, if longer.

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Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

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

-Publisher FASB

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-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.6(a))

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Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

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- Definition

Carrying amount as of the balance sheet date of expenditures made, not otherwise specified in the taxonomy, in advance of the timing of recognition of expenses which are expected to be charged against earnings within one year or the normal operating cycle, if longer.

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Section A

-Paragraph 4

-Chapter 3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The total of the amounts paid in advance for capitalized costs that will be expensed with the passage of time or the occurrence of a triggering event, and will be charged against earnings within one year or the normal operating cycle, if longer, and the aggregate carrying amount of current assets, as of the balance sheet date, not separately presented elsewhere in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

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

-Publisher SEC

-Name Regulation S-X (SX)

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-Publisher AICPA

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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