Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Stockholders' equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares (in shares)	500,000,000	500,000,000
Common stock, issued shares (in shares)	31,488,204	31,488,204
Common stock, outstanding shares (in shares)	24,833,301	24,833,301
Warrants to purchase common stock (in shares)	329,932
Exercise price of warrants (in dollars per share)	$ 2.94