v3.3.1.900

Stock‑Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of stock option activity |
|  | Outstanding Options |
|  |  |  |  |  |  |  | Weighted- |  |  |
|  |  |  |  |  | Weighted- |  | Average |  |  |
|  | Shares |  |  |  | Average |  | Remaining |  | Aggregate |
|  | Available for |  | Number of |  | Exercise |  | Contractual |  | Intrinsic |
(in thousands, except for contractual life and exercise price) |  | Grant |  | Shares |  | Price |  | Life |  | Value |
|  |  |  |  |  |  |  |  | (In years) |  |  |
Balance at December 31, 2014 |  | 294 |  | 8,463 |  | $ | 2.28 |  | 8.83 |  | $ | 43,659 |
Additional shares authorized |  | 4,985 |  | — |  |  |  |  |  |  |  |  |
Options granted |  | (2,181) |  | 2,181 |  | $ | 10.16 |  |  |  |  |  |
Options exercised |  | — |  | (683) |  | $ | 1.72 |  |  |  |  |  |
Options forfeited |  | 645 |  | (645) |  | $ | 5.25 |  |  |  |  |  |
Balance at December 31, 2015 |  | 3,743 |  | 9,316 |  | $ | 3.96 |  | 8.31 |  | $ | 63,713 |
Exercisable at December 31, 2015 |  |  |  | 5,602 |  | $ | 1.90 |  | 5.31 |  | $ | 49,880 |
Vested and expected to vest at December 31, 2015 |  |  |  | 8,414 |  | $ | 3.72 |  | 7.32 |  | $ | 59,529 |
Summary of stock-based compensation expenses |
|  | Year ended December 31, |
|  | 2015 |  | 2014 |  | 2013 |
|  | Employee |  | Non-Employee |  | Total |  | Employee |  | Non-Employee |  | Total |  | Employee |  | Non-Employee |  | Total |
|  | (in thousands) |
Cost of revenues |  | $ | 351 |  | $ | 241 |  | $ | 592 |  | $ | 262 |  | $ | 29 |  | $ | 291 |  | $ | 55 |  | $ | 7 |  | $ | 62 |
Research and development |  |  | 1,566 |  |  | 9 |  |  | 1,575 |  |  | 1,563 |  |  | 30 |  |  | 1,593 |  |  | 612 |  |  | 4 |  |  | 616 |
Selling, general and administrative |  |  | 4,993 |  |  | 166 |  |  | 5,159 |  |  | 3,180 |  |  | 93 |  |  | 3,273 |  |  | 970 |  |  | 9 |  |  | 979 |
Total |  | $ | 6,910 |  | $ | 416 |  | $ | 7,326 |  | $ | 5,005 |  | $ | 152 |  | $ | 5,157 |  |  | 1,637 |  | $ | 20 |  | $ | 1,657 |
Employee stock options |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Schedule of assumptions used in valuation of fair value of employee stock options |
|  | Year ended December 31,
|  | 2015 |  |  | 2014 |  |  | 2013 |
Expected term |  | 5.6 |  | — | 10.0 |  |  | 4.91 |  | — | 7.06 |  |  | 6.0 |
Expected volatility |  | 69.7 | % | — | 78.8 | % |  | 73.4 | % | — | 87.0 | % |  | 63.7 | % | — | 85.7 | %
Expected dividend rate |  |  |  |  | 0 | % |  |  |  |  | 0 | % |  |  |  |  | 0 | %
Risk-free interest rate |  | 1.56 | % | — | 2.32 | % |  | 1.65 | % | — | 2.04 | % |  | 0.44 | % | — | 2.86 | %
Non-employee stock options |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Schedule of assumptions used in valuation of fair value of employee stock options |
|  | Year ended December 31,
|  | 2015 |  |  | 2014 |  |  | 2013 |
Expected term |  | 4.9 |  | — | 9.8 |  |  | 4.4 |  | — | 10.0 |  |  | 8.4 |
Expected volatility |  | 70.2 | % | — | 75.4 | % |  | 71.9 | % | — | 80.2 | % |  | 75.6 | % | — | 81.5 | %
Expected dividend rate |  |  |  |  | 0 | % |  |  |  |  | 0 | % |  |  |  |  | 0 | %
Risk-free interest rate |  | 1.74 | % | — | 2.24 | % |  | 1.41 | % | — | 2.61 | % |  | 1.44 | % | — | 2.51 | %

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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year. + 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 (c)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + 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) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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