Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Stockholders' Equity
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	15,000,000	15,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock issued (in shares)	61,142,756	52,424,649
Common stock, shares outstanding (in shares)	61,142,756	52,424,649