FINANCIAL INSTRUMENTS 2 (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Jun. 30, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total US Dollar floating rate and fixed rate debt	192,857,000	$ 459,078,000
Front Century [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of vessels carried at fair value using level 3 inputs	21,100,000	24,200,000	25,800,000
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	64,080,000	53,759,000
Restricted cash and investments	42,074,000	68,363,000
Marketable securities	2,624,000	3,479,000
First Preferred Mortgage Term Notes, Fair Value Disclosure 2		129,381,000
8.04% First Preferred Mortgage Term Notes	33,143,000	70,696,000
Convertible bond (4.5%)	114,347,000	140,315,000
Total US Dollar floating rate and fixed rate debt	29,500,000
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	64,080,000	53,759,000
Restricted cash and investments	42,074,000	68,363,000
Marketable securities	2,624,000	3,479,000
First Preferred Mortgage Term Notes, Fair Value Disclosure 2		0
8.04% First Preferred Mortgage Term Notes	0
Convertible bond (4.5%)	0	0
Total US Dollar floating rate and fixed rate debt	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Restricted cash and investments	0	0
Marketable securities	0	0
First Preferred Mortgage Term Notes, Fair Value Disclosure 2		129,381,000
8.04% First Preferred Mortgage Term Notes	33,143,000	70,696,000
Convertible bond (4.5%)	114,347,000	140,315,000
Total US Dollar floating rate and fixed rate debt	29,500,000
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Restricted cash and investments	0	0
Marketable securities	0	0
First Preferred Mortgage Term Notes, Fair Value Disclosure 2		0
8.04% First Preferred Mortgage Term Notes	0
Convertible bond (4.5%)	0	0
Total US Dollar floating rate and fixed rate debt	0
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	64,080,000	53,759,000
Restricted cash and investments	42,074,000	68,363,000
Marketable securities	2,624,000	3,479,000
First Preferred Mortgage Term Notes, Fair Value Disclosure 2	0	185,838,000
8.04% First Preferred Mortgage Term Notes	36,657,000	83,240,000
Convertible bond (4.5%)	126,700,000	190,000,000
Total US Dollar floating rate and fixed rate debt	29,500,000	0
Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	64,080,000	53,759,000
Restricted cash and investments	42,074,000	68,363,000
Marketable securities	2,624,000	3,479,000
First Preferred Mortgage Term Notes, Fair Value Disclosure 2	0	129,381,000
8.04% First Preferred Mortgage Term Notes	33,143,000	70,696,000
Convertible bond (4.5%)	114,347,000	140,315,000
Total US Dollar floating rate and fixed rate debt	29,500,000	$ 0
8.04% First Preferred Mortgage Term Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate, minimum	7.84%
Stated interest rate, maximum	8.04%

Fair value of vessels carried at fair value using level 3 inputs

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. This item represents first preferred mortgage term notes payable (7.84% - 8.04%) as of the balance sheet date.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. This item represents marketable securities which are intended to be held for less than one year or the normal operating cycle, whichever is longer.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. This item includes restricted cash and investments which are restricted as to withdrawal or usage.

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The total carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate and rate subject to change from time to time.

+ References

No definition available.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Publisher FASB

-Name Accounting Standards Codification

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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-Publisher FASB

-Name Accounting Standards Codification

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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Maximum contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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Minimum contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher SEC

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-Section 02

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