SIGNIFICANT ACCOUNTING POLICIES (Schedule of Stock-Based Compensation Assumptions) (Details)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Risk-free interest rate	0.75%	2.23%	1.62%
Dividend yield	0.00%	0.00%
Weighted average dividend yield	0.00%	0.00%	5.65%
Weighted average volatility	53.76%	56.29%	63.67%
Expected term (years)	4 years 1 month 1 day	3 years 8 months 25 days	4 years 7 months 4 days
Minimum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Dividend yield			0.00%
Expected volatility	45.60%	47.31%	62.77%
Maximum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Dividend yield			7.83%
Expected volatility	61.90%	65.27%	64.56%

Fair Value Assumptions Weighted Average Expected Dividend Rate

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- Definition

Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

+ 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 (e)

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

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

+ Details

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

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- Definition

Weighted average expected volatility of stock price.

+ References

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