Preferred Stock (Tables)

3 Months Ended

Mar. 31, 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 three months ended March 31, 2015 was as follows:

	(in thousands)
Redeemable Convertible Preferred Stock
Series B	$	5,216
Series B-1		3,513
Series C		416
Series D		1,860
Total adjustment to redemption value on redeemable convertible preferred stock	$	11,005

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 three months ended March 31, 2015:

Expected term (in years)	1.1
Expected volatility	81	%
Risk-free interest rate	0.3	%
Expected dividend rate	—	%