Convertible Preferred Stock and Stock Warrants	12 Months Ended
Dec. 31, 2014
Warrants and Rights Note Disclosure [Abstract]
Convertible Preferred Stock and Stock Warrants	Convertible Preferred Stock and Stock Warrants In August 2009, the Company sold convertible preferred stock with detachable warrants to purchase shares of the Company's common stock. In February 2011, the Company exercised its contractual right to mandatorily convert all outstanding shares of convertible preferred stock into shares of common stock. Currently, the Company has no issued or outstanding shares of preferred stock. Due to the anti-dilution price adjustment provisions established at the issuance date, the warrants were deemed to be a liability and were recorded at fair value at the date of issuance. The warrant liability was adjusted to fair value at the end of each reporting period through the statement of operations during the period the anti-dilution price adjustment provisions were in effect. On June 14, 2012, contractual provisions within the Company's warrant agreements were modified to eliminate the anti-dilution price adjustment provisions of the warrants and remove the cash settlement provisions in the event of a change of control. The amended warrants then qualified to be classified as equity. Accordingly, the Company revalued the warrants as of June 14, 2012, the date of contractual amendment. The change in fair value of the warrant liability compared to the fair value on December 31, 2011, $2.6 million, was recognized in income during 2012. The revalued warrant liability of $14.0 million was reclassified to additional paid-in capital on June 14, 2012. There were no longer fair value adjustments because the warrants continued to meet the criteria for equity classification. The Company used the Black-Scholes option-pricing model to estimate the fair value of the warrant liability for each reporting period. On June 14, 2012, the date the warrants were amended, inputs into the fair value calculation included the actual remaining term of the warrants, a volatility rate of 58.1%, a risk-free rate of return of 0.36%, and an assumed dividend rate of zero. During the years ended December 31, 2013 and 2012, warrants were exercised to purchase 267,000 shares and 348,350 shares, respectively, of the Company’s common stock for which the Company received cash proceeds of $0.3 million and $0.4 million, respectively. On February 7, 2014, warrants were exercised to purchase 1,277,250 shares of the Company’s common stock at $1.21 per share. The Company received cash proceeds of $1.5 million in connection with the warrants exercised. Following this exercise, the Company no longer has any outstanding warrants.

Convertible Preferred Stock and Stock Warrants

In August 2009, the Company sold convertible preferred stock with detachable warrants to purchase shares of the Company's common stock. In February 2011, the Company exercised its contractual right to mandatorily convert all outstanding shares of convertible preferred stock into shares of common stock. Currently, the Company has no issued or outstanding shares of preferred stock.

Due to the anti-dilution price adjustment provisions established at the issuance date, the warrants were deemed to be a liability and were recorded at fair value at the date of issuance. The warrant liability was adjusted to fair value at the end of each reporting period through the statement of operations during the period the anti-dilution price adjustment provisions were in effect. On June 14, 2012, contractual provisions within the Company's warrant agreements were modified to eliminate the anti-dilution price adjustment provisions of the warrants and remove the cash settlement provisions in the event of a change of control. The amended warrants then qualified to be classified as equity. Accordingly, the Company revalued the warrants as of June 14, 2012, the date of contractual amendment. The change in fair value of the warrant liability compared to the fair value on December 31, 2011, $2.6 million, was recognized in income during 2012. The revalued warrant liability of $14.0 million was reclassified to additional paid-in capital on June 14, 2012. There were no longer fair value adjustments because the warrants continued to meet the criteria for equity classification.

The Company used the Black-Scholes option-pricing model to estimate the fair value of the warrant liability for each reporting period. On June 14, 2012, the date the warrants were amended, inputs into the fair value calculation included the actual remaining term of the warrants, a volatility rate of 58.1%, a risk-free rate of return of 0.36%, and an assumed dividend rate of zero.

During the years ended December 31, 2013 and 2012, warrants were exercised to purchase 267,000 shares and 348,350 shares, respectively, of the Company’s common stock for which the Company received cash proceeds of $0.3 million and $0.4 million, respectively.

On February 7, 2014, warrants were exercised to purchase 1,277,250 shares of the Company’s common stock at $1.21 per share. The Company received cash proceeds of $1.5 million in connection with the warrants exercised. Following this exercise, the Company no longer has any outstanding warrants.