CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)
Dec. 31, 2013
Dec. 31, 2012
Common stock, par value $ 0.01 $ 0.01
Common stock, authorized 150,000,000 100,000,000
Common stock, issued 84,502,653 81,889,226
Common stock, outstanding 84,502,653 81,889,226
Series A convertible preferred stock [Member]
   
Preferred stock, par value $ 0.01 $ 0.01
Preferred stock, authorized 5,000,000 5,000,000
Preferred stock, issued 0 0
Preferred stock, outstanding 0 0