Common Stock (Tables)

6 Months Ended

Jun. 30, 2015

Equity [Abstract]

Schedule of Shares Reserved for Future Issuance

The shares reserved for future issuance as of June 30, 2015 and December 31, 2014 consisted of the following:

(in thousands)	As of June 30, 2015		As of December 31, 2014
Options to purchase common stock		19,426		19,567
Common stock warrants		377		2,381
Conversion premium on the Notes		25,000		25,000