Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Common Stock [Member] | IPO [Member] | |||
| Stock issuance cost | $ 2,620 | ||
| Common Stock [Member] | Secondary Offering [Member] | |||
| Stock issuance cost | $ 473 | $ 866 | |
| Series D-2 Preferred [Member] | Issuance Date of February 2014 [Member] | |||
| Stock, issuance price per share | $ 0.76 | ||
| Stock issuance cost | $ 23 | ||
| Series E Preferred Stock [Member] | Issuance Date of February 2014 [Member] | |||
| Stock, issuance price per share | $ 1.13 | ||
| Stock issuance cost | $ 184 | ||