Condensed Consolidated Financial Statements Detail - Reconciliation of the Numerator (Net Loss) and the Denominator (Number of Shares) Used in the Calculation of Basic and Diluted Net Loss Per Share Available to Common Stockholders (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Numerator
Net loss	$ (10,715)	$ (8,365)
Deemed dividend on convertible preferred stock	(5,603)
Net loss available to common stockholders, basic and diluted	$ (16,318)	$ (8,365)
Denominator
Weighted average shares outstanding used for basic and diluted net loss per share available to common stockholders	6,887	5,978

Condensed Consolidated Financial Statements Detail - Reconciliation of the Numerator (Net Loss) and the Denominator (Number of Shares) Used in the Calculation of Basic and Diluted Net Loss Per Share Available to Common Stockholders (Details) - USD ($)
shares in Thousands, $ in Thousands

3 Months Ended

Mar. 31, 2017

Mar. 31, 2016

Numerator

Net loss

$ (10,715)

$ (8,365)

Deemed dividend on convertible preferred stock

(5,603)

Net loss available to common stockholders, basic and diluted

$ (16,318)

$ (8,365)

Denominator

Weighted average shares outstanding used for basic and diluted net loss per share available to common stockholders

6,887

5,978