FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 3) (Recurring basis, USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Equity derivative contracts
Changes in Level 3 Financial Assets measured at fair value
Beginning Balance	$ 1,937
Total realized and unrealized gains (losses) included in Income	(2,475)
Purchases	566	1,937
Ending Balance	28	1,937
Unrealized gains (losses) for Level 3 Assets outstanding at end of the period	(2,475)
Convertible note receivable, available-for-sale
Changes in Level 3 Financial Assets measured at fair value
Beginning Balance	5,362
Total realized and unrealized gains (losses) included in Income	(5,362)
Purchases		5,362
Ending Balance		5,362
Unrealized gains (losses) for Level 3 Assets outstanding at end of the period	$ (5,362)

Represents amount of unrealized gain (loss) arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

No definition available.

+ Details

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- Definition

Amount of gain (loss) recognized in earnings, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

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- Definition

Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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