STOCKHOLDERS' EQUITY

12 Months Ended

Dec. 31, 2012

Stockholders' Equity Note [Abstract]

STOCKHOLDERS' EQUITY

9. STOCKHOLDERS’ EQUITY

Preferred Stock

We are authorized to issue up to one million shares of preferred stock. As of December 31, 2012 and 2011, there were no outstanding shares of preferred stock. Our Board of Directors will determine the terms of the preferred stock if and when the shares are issued.

Common Stock

Our amended Certificate of Incorporation authorizes the issuance of up to 100 million shares of $0.01 par value common stock.

In January 2011, we completed a stock offering in which we sold 8,050,000 shares of common stock at a price of $6.15 per share for net proceeds of $46.8 million after commissions and offering expenses.

In April 2012, we completed a stock offering in which we sold 8,222,500 shares of common stock at a price of $7.30 per share for net proceeds of $56.3 million after commissions and offering expenses.

At December 31, 2012, we have 585,033 common shares reserved for future issuance under the Employee Stock Purchase Plan (“Purchase Plan”) and for the exercise of common stock options pursuant to the 1994 Amended and Restated Equity Incentive Plan (“Equity Incentive Plan”) and the 1996 Amended and Restated Director Stock Option Plan (“Director Plan”).