v3.3.1.900

Stock‑Based Compensation (Assumptions) (Details) - shares shares in Thousands | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Employee and non-employee stock options |  |  |
Stock Based Compensation |  |  |
Options granted (in shares) | 2,181 |  |
Employee stock options |  |  |
Valuation of Stock Option Grants to Employees |  |  |
Expected term |  |  | 6 years
Expected volatility, minimum | 69.70% | 73.40% | 63.70%
Expected volatility, maximum | 78.80% | 87.00% | 85.70%
Expected dividend rate | 0.00% | 0.00% | 0.00%
Risk‑free interest rate, minimum | 1.56% | 1.65% | 0.44%
Risk‑free interest rate, maximum | 2.32% | 2.04% | 2.86%
Employee stock options | Minimum |  |  |
Valuation of Stock Option Grants to Employees |  |  |
Expected term | 5 years 7 months 6 days | 4 years 10 months 28 days |
Employee stock options | Maximum |  |  |
Valuation of Stock Option Grants to Employees |  |  |
Expected term | 10 years | 7 years 22 days |
Non-employee stock options |  |  |
Stock Based Compensation |  |  |
Options granted (in shares) | 200 |  |
Options unvested (in shares) | 100 |  |
Valuation of Stock Option Grants to Employees |  |  |
Expected term |  |  | 8 years 4 months 24 days
Expected volatility, minimum | 70.20% | 71.90% | 75.60%
Expected volatility, maximum | 75.40% | 80.20% | 81.50%
Expected dividend rate | 0.00% | 0.00% | 0.00%
Risk‑free interest rate, minimum | 1.74% | 1.41% | 1.44%
Risk‑free interest rate, maximum | 2.24% | 2.61% | 2.51%
Non-employee stock options | Minimum |  |  |
Valuation of Stock Option Grants to Employees |  |  |
Expected term | 4 years 10 months 24 days | 4 years 4 months 24 days |
Non-employee stock options | Maximum |  |  |
Valuation of Stock Option Grants to Employees |  |  |
Expected term | 9 years 9 months 18 days | 10 years |

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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 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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + 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 Number of non-vested options outstanding. + References No definition available. + Details
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