v3.6.0.2

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) shares in Thousands, $ in Thousands | Common stock | Additional Paid-in Capital | Notes Receivable from Officers | Accumulated Other Comprehensive Loss | Accumulated Deficit | Total
--- | --- | --- | --- | --- | --- | ---
Balance at Dec. 31, 2013 | $ 1 | $ 3,338 | $ (192) |  | $ (174,656) | $ (171,509)
Balance (in shares) at Dec. 31, 2013 | 6,561 |  |  |  |  |
Issuance of common stock upon exercise of stock options |  | 169 |  |  |  | 169
Issuance of common stock upon exercise of stock options (in shares) | 318 |  |  |  |  |
Stock based compensation |  | 5,157 |  |  |  | 5,157
Net loss |  |  |  |  | (5,152) | (5,152)
Balance at Dec. 31, 2014 | $ 1 | 8,664 | (192) |  | (179,808) | (171,335)
Balance (in shares) at Dec. 31, 2014 | 6,879 |  |  |  |  |
Issuance of common stock upon exercise of stock options |  | 1,258 |  |  |  | 1,258
Issuance of common stock upon exercise of stock options (in shares) | 1,170 |  |  |  |  |
Stock based compensation |  | 7,326 |  |  |  | 7,326
Officer loan receivable repayment |  |  | $ 192 |  |  | 192
Issuance of common stock in connection with the initial public offering | $ 1 | 182,465 |  |  |  | 182,466
Issuance of common stock in connection with the initial public offering (in shares) | 10,900 |  |  |  |  |
Issuance costs of Initial Public Offering |  | (4,036) |  |  |  | (4,036)
Conversion of all Preferred Stock into Common Stock upon the completion of the initial public offering | $ 3 | 240,582 |  |  |  | 240,585
Conversion of all Preferred Stock into Common Stock upon the completion of the initial public offering (in shares) | 31,397 |  |  |  |  |
Unrealized gain (loss) on available-for-sale investments |  |  |  | $ (1,416) |  | (1,416)
Net loss |  |  |  |  | (70,275) | (70,275)
Balance at Dec. 31, 2015 | $ 5 | 436,259 |  | (1,416) | (250,083) | $ 184,765
Balance (in shares) at Dec. 31, 2015 | 50,346 |  |  |  |  | 50,346
Issuance of common stock upon exercise of stock options |  | 3,595 |  |  |  | $ 3,595
Issuance of common stock upon exercise of stock options (in shares) | 1,913 |  |  |  |  |
Issuance of common stock under employee stock purchase plan |  | 2,589 |  |  |  | 2,589
Issuance of common stock under employee stock purchase plan (in shares) | 341 |  |  |  |  |
Vesting of restricted stock (in shares) | 65 |  |  |  |  |
Stock based compensation |  | 10,601 |  |  |  | 10,601
Unrealized gain (loss) on available-for-sale investments |  |  |  | 691 |  | 691
Net loss |  |  |  |  | (95,765) | (95,765)
Balance at Dec. 31, 2016 | $ 5 | $ 453,044 |  | $ (725) | $ (345,848) | $ 106,476
Balance (in shares) at Dec. 31, 2016 | 52,665 |  |  |  |  | 52,665

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