Consolidated Balance Sheets Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	160,000,000	160,000,000
Common stock, shares issued	56,143,986	55,587,167
Common stock, shares outstanding	56,143,986	55,587,167