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Stockholders' Equity (Deficiency) (Summary of Compensation Expense for Stock Options Granted to Employees) (Details) (Stock Incentive Plan To Employees And Directors [Member])
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3 Months Ended | 12 Months Ended | ||
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Mar. 31, 2013
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Mar. 31, 2012
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Dec. 31, 2012
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Dec. 31, 2011
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Stock Incentive Plan To Employees And Directors [Member]
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| Expected life (years) minimum | 3 years 6 months | 3 years 6 months | 2 years 6 months | |
| Expected life (years) maximum | 3 years 9 months | 3 years 6 months | 3 years 9 months 18 days | |
| Expected volatility minimum | 46.30% | 44.20% | 44.20% | |
| Expected volatility maximum | 46.50% | 44.20% | 50.90% | |
| Weighted-average volatility | 46.50% | 44.20% | 49.00% | |
| Risk-free interest rate, Minimum | 0.36% | 0.56% | 0.31% | |
| Risk-free interest rate, Maximum | 0.44% | 0.60% | 0.60% | |
| Dividend yield | 0.00% | 0.00% | 0.00% | |
| Expected forfeiture rate | 3.90% | 2.00% | 1.70% | |
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- Definition
Custom Element. No definition available.
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- Definition
Custom Element. No definition available.
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- Definition
Custom Element. No definition available.
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- Definition
The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. No definition available.
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- Definition
The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. No definition available.
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- Definition
The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. No definition available.
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- Definition
The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. No definition available.
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- Definition
The range of expected volatilities used and the weighted-average expected volatility for an entity using a valuation technique with different volatilities during the contractual term. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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