v3.6.0.2

Stock-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2016
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, 2015 |  | 3,743 |  | 9,316 |  | $ | 3.96 |  | 8.31 |  | $ | 63,713 |
Additional shares authorized |  | 2,014 |  | — |  |  |  |  |  |  |  |  |
Options granted |  | (2,558) |  | 2,558 |  | $ | 10.23 |  |  |  |  |  |
Options exercised |  | — |  | (1,915) |  | $ | 1.88 |  |  |  |  |  |
Options forfeited |  | 916 |  | (916) |  | $ | 8.28 |  |  |  |  |  |
Balance at December 31, 2016 |  | 4,115 |  | 9,043 |  | $ | 5.72 |  | 7.55 |  | $ | 55,396 |
Exercisable at December 31, 2016 |  |  |  | 5,054 |  | $ | 3.10 |  | 6.51 |  | $ | 43,938 |
Vested and expected to vest at December 31, 2016 |  |  |  | 9,039 |  | $ | 5.72 |  | 7.55 |  | $ | 55,386 |
Restricted stock units |
|  |  |  | Weighted-Average Grant Date |
|  | Shares |  | Fair Value |
Balance at December 31, 2015 |  |  | — |  | $ | — |
Granted |  |  | 212 |  | $ | 9.76 |
Vested |  |  | (40) |  | $ | 9.59 |
Canceled/forfeited |  |  | (13) |  | $ | 9.81 |
Balance at December 31, 2016 |  |  | 159 |  | $ | 9.80 |
Summary of stock-based compensation expenses |
|  | Year ended December 31, |
|  | 2016 |  | 2015 |  | 2014 |
|  | Employee |  | Non-Employee |  | Total |  | Employee |  | Non-Employee |  | Total |  | Employee |  | Non-Employee |  | Total |
|  | (in thousands) |
Cost of revenues |  | $ | 651 |  | $ | (10) |  | $ | 641 |  | $ | 351 |  | $ | 241 |  | $ | 592 |  | $ | 262 |  | $ | 29 |  | $ | 291 |
Research and development |  |  | 2,829 |  |  | 24 |  |  | 2,853 |  |  | 1,566 |  |  | 9 |  |  | 1,575 |  |  | 1,563 |  |  | 30 |  |  | 1,593 |
Selling, general and administrative |  |  | 6,837 |  |  | 270 |  |  | 7,107 |  |  | 4,993 |  |  | 166 |  |  | 5,159 |  |  | 3,180 |  |  | 93 |  |  | 3,273 |
Total |  | $ | 10,317 |  | $ | 284 |  | $ | 10,601 |  | $ | 6,910 |  | $ | 416 |  | $ | 7,326 |  |  | 5,005 |  | $ | 152 |  | $ | 5,157 |
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,
|  | 2016 |  |  | 2015 |  |  | 2014 |
Expected term |  | 5.1 |  | — | 5.2 |  |  | 5.6 |  | — | 10.0 |  |  | 4.9 — 7.1 |
Expected volatility |  | 62.2 | % | — | 72.5 | % |  | 69.7 | % | — | 78.8 | % |  | 73.4 | % | — | 87.0 | %
Expected dividend rate |  |  |  |  | 0 | % |  |  |  |  | 0 | % |  |  |  |  | 0 | %
Risk-free interest rate |  | 0.97 | % | — | 1.92 | % |  | 1.56 | % | — | 2.32 | % |  | 1.65 | % | — | 2.04 | %
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,
|  | 2016 |  |  | 2015 |  |  | 2014 |
Expected term |  | 2.7 |  | — | 3.2 |  |  | 4.9 |  | — | 9.8 |  |  | 4.4 — 10.0 |
Expected volatility |  | 50.9 | % | — | 72.6 | % |  | 70.2 | % | — | 75.4 | % |  | 71.9 | % | — | 80.2 | %
Expected dividend rate |  |  |  |  | 0 | % |  |  |  |  | 0 | % |  |  |  |  | 0 | %
Risk-free interest rate |  | 0.68 | % | — | 1.38 | % |  | 1.74 | % | — | 2.24 | % |  | 1.41 | % | — | 2.61 | %

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- Definition Tabular disclosure of the number, aggregate intrinsic value (except for nonpublic entities), and weighted-average remaining contractual term for both restricted stock units outstanding and restricted stock units fully vested and expected to vest at the date of the latest statement of financial position. + 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 (e)(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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