v3.8.0.1

Note 14 - Net Loss Per Share of Common Stock (Tables) | 12 Months Ended
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Dec. 31, 2017
Notes Tables |
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] |
|  | Years Ended December 31, |
|  | 201 7 |  |  | 201 6 |  |  | 201 5 |
|  | (in thousands, except share and per share amounts) |
Numerator: |  |  |  |  |  |  |  |  |  |  |  |
Net loss used to compute net loss per share |  |  |  |  |  |  |  |  |  |  |  |
Basic |  | $ | (51,508 | ) |  | $ | (43,157 | ) |  | $ | (24,399 | )
Adjustments for change in fair value of warrant liability |  |  | — |  |  |  | — |  |  |  | (2,120 | )
Diluted |  | $ | (51,508 | ) |  | $ | (43,157 | ) |  | $ | (26,519 | )
Denominator: |  |  |  |  |  |  |  |  |  |  |  |
Weighted average shares outstanding used to compute net loss per share: |  |  |  |  |  |  |  |  |  |  |  |
Basic |  |  | 46,883,535 |  |  |  | 45,313,118 |  |  |  | 44,300,099 |
Dilutive effect of warrants |  |  | — |  |  |  | — |  |  |  | 168,341 |
Diluted |  |  | 46,883,535 |  |  |  | 45,313,118 |  |  |  | 44,468,440 |
Net loss per share —basic |  | $ | (1.10 | ) |  | $ | (0.95 | ) |  | $ | (0.55 | )
Net loss per share —diluted |  | $ | (1.10 | ) |  | $ | (0.95 | ) |  | $ | (0.60 | )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] |
|  | Year Ended December 31, |
|  | 201 7 |  |  | 201 6 |  |  | 201 5 |
ESPP and stock options to purchase common stock |  |  | 8,767,783 |  |  |  | 6,395,879 |  |  |  | 4,699,121 |
Convertible debt into common stock |  |  | — |  |  |  | 553,763 |  |  |  | 553,763 |
Common stock warrants |  |  | 176,730 |  |  |  | 692,611 |  |  |  | 180,155 |

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- Definition Tabular disclosure of securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented, by antidilutive securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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- Definition Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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