v2.4.0.8

Assumptions Used to Estimate Fair Value of Stock Options Granted and Stock Purchase Rights Granted Under our Employee Stock Purchase Plan (Detail) | 9 Months Ended
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Sep. 30, 2014 | Sep. 30, 2013
Options |  |
Expected volatility, minimum | 42.39% | 50.03%
Expected volatility, maximum | 49.94% | 53.58%
Risk-free interest rate, minimum | 1.62% | 0.77%
Risk-free interest rate, maximum | 1.78% | 1.40%
Expected dividend yield | 0.00% | 0.00%
Options | Minimum |  |
Expected term (years) | 5 years 6 months 11 days | 5 years 7 months 10 days
Options | Maximum |  |
Expected term (years) | 5 years 6 months 26 days | 5 years 8 months 1 day
Employee Stock |  |
Expected volatility, minimum | 21.40% | 28.63%
Expected volatility, maximum | 62.24% | 41.52%
Expected term (years) | 1 year 3 months | 1 year 3 months
Risk-free interest rate, minimum | 0.05% | 0.08%
Risk-free interest rate, maximum | 0.47% | 0.35%
Expected dividend yield | 0.00% | 0.00%

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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section D -Subsection 2 + Details
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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. + References No definition available. + Details
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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. + References No definition available. + Details
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- Definition The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. + References No definition available. + Details
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. + References No definition available. + Details
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