Preferred Stock (Tables)

6 Months Ended

Jun. 30, 2016

Equity [Abstract]

Change in Redemption Value of Convertible Preferred Stock

The change in the redemption value of the redeemable convertible preferred stock for the six months ended June 30, 2015 was as follows:

Redeemable Convertible Preferred Stock	(in thousands)
Series B	$	23,184
Series B-1		16,307
Series C		20,359
Series D		92,035
Total adjustment to redemption value on redeemable convertible preferred stock	$	151,885

Summary of Assumptions used to Determine Fair Value of Temporary Equity

As the redemption value for the redeemable convertible preferred stock was at times based on fair market value, the Company determined the fair value of the redeemable convertible preferred stock using a combination of the OPM and/or the PWERM models, or the fair value of the Company’s common stock. The following assumptions were used in the OPM to determine fair value of the redeemable convertible preferred stock for the six months ended June 30, 2015:

Expected term (in years)	0.9
Expected volatility	66	%
Risk-free interest rate	0.2	%
Expected dividend rate	—	%