v3.8.0.1
Consolidated Statements of Stockholders' (Deficit) Equity - USD ($)
$ in Thousands
Common Stock [Member]
Additional Paid-in Capital [Member]
Retained Earnings [Member]
AOCI Attributable to Parent [Member]
Total
Balance (in shares) at Dec. 31, 2014 43,712,363        
Balance at Dec. 31, 2014 $ 43 $ 225,423 $ (178,806) $ (4) $ 46,656
Stock-based compensation 5,010 5,010
Issuance of common stock upon exercise of stock options (in shares) 938,497        
Issuance of common stock upon exercise of stock options $ 1 2,769 $ 2,770
Issuance of common stock upon exercise of stock warrants (in shares) 527,101       527,101
Issuance of common stock upon exercise of stock warrants $ 1 2,543 $ 2,544
Modification of warrants 100 100
Issuance of common stock upon ESPP purchase (in shares) 95,811        
Issuance of common stock upon ESPP purchase 429 429
Change in unrealized gains and losses on investments 3 3
Net loss (24,399) (24,399)
Balance (in shares) at Dec. 31, 2015 45,273,772        
Balance at Dec. 31, 2015 $ 45 236,274 (203,205) (1) 33,113
Stock-based compensation 4,479 4,479
Modification of warrants 45 45
Issuance of common stock upon ESPP purchase (in shares) 60,018        
Issuance of common stock upon ESPP purchase 179 179
Change in unrealized gains and losses on investments 4 4
Net loss (43,157) (43,157)
Balance (in shares) at Dec. 31, 2016 45,333,790        
Balance at Dec. 31, 2016 $ 45 240,977 (246,362) 3 (5,337)
Stock-based compensation 4,294 $ 4,294
Issuance of common stock upon exercise of stock options (in shares) 69,372       69,372
Issuance of common stock upon exercise of stock options 105 $ 105
Issuance of common stock upon ESPP purchase (in shares) 94,893        
Issuance of common stock upon ESPP purchase 246 246
Change in unrealized gains and losses on investments (3) (3)
Net loss (51,508) $ (51,508)
Net proceeds from issuance of common stock in connection with equity financings (in shares) 5,401,099       5,400,000
Net proceeds from issuance of common stock in connection with equity financings $ 6 15,688 $ 15,694
Balance (in shares) at Dec. 31, 2017 50,899,154        
Balance at Dec. 31, 2017 $ 51 $ 261,310 $ (297,870) $ (36,509)