Convertible Preferred Stock	12 Months Ended
Dec. 31, 2018
Equity [Abstract]
Convertible Preferred Stock	8. Convertible Preferred Stock Prior to its initial public offering, the Company had outstanding 15,208,048 shares of convertible preferred stock. Each share of preferred stock was convertible to one share of common stock. Upon the closing of the Company’s initial public offering on November 11, 2014, all shares of outstanding redeemable convertible preferred stock were automatically converted to 15,208,048 shares of the Company’s common stock.

The entire disclosure for terms, amounts, nature of changes, rights and privileges, dividends, and other matters related to preferred stock.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-URI http://asc.fasb.org/topic&trid=2208762

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