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Organization and Summary of Significant Accounting Policies (Assumptions Used To Calculate Fair Value) (Details) (USD $)
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12 Months Ended | ||
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Dec. 31, 2012
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Dec. 31, 2011
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Dec. 31, 2010
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Expected volatility, minimum | 63.00% | 64.00% | 61.00% |
| Expected volatility, maximum | 72.00% | 71.00% | 68.00% |
| Weighted-average volatility | 65.00% | 69.00% | 66.00% |
| Expected dividends | |||
| Risk-free rate, minimum | 0.60% | 1.30% | 1.70% |
| Risk-free rate, maximum | 1.20% | 2.40% | 2.40% |
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Minimum [Member]
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Expected term | 5 years | 5 years 3 months 18 days | 6 years |
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Maximum [Member]
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Expected term | 6 years 3 months 18 days | 6 years 3 months 18 days | 6 years 3 months 18 days |
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- Definition
The estimated amount of dividends to be paid to holders of the underlying shares (expected dividends) over the option's term. Dividends are taken into account because payment of dividends to shareholders reduces the fair value of the underlying shares, and option holders generally do not receive dividends. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The estimated measure of the 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. 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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- Details
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