Net Loss per Share (Tables)

12 Months Ended

Dec. 31, 2015

Net Loss per Share

Basic and diluted net loss per common share

	Year ended December 31,
(in thousands, except per share data)	2015		2014		2013
Basic and diluted loss per share:
Net loss	$	(70,275)	$	(5,152)	$	(37,110)
Net loss attributable to common shares, basic and diluted		(70,275)		(5,152)		(37,110)
Weighted-average common shares outstanding		27,687		6,670		6,093
Less:  weighted-average unvested common shares subject to repurchase		(1,483)		(1,870)		(2,252)
Weighted-average number of shares used in computing net loss per share, basic and diluted		26,204		4,800		3,841
Basic and diluted net loss per share	$	(2.68)	$	(1.07)	$	(9.66)

Potentially dilutive shares not included in the calculation of dilutive EPS

	Year ended December 31,
	2015	2014	2013
Options to purchase common stock	9,316	8,450	4,406
Warrants to purchase common stock	377	864	410
Common stock subject to repurchase	1,307	1,690	2,077
Convertible preferred stock	—	31,397	27,048
	11,000	42,401	33,941