Balance Sheets Parenthetical (USD $)	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Shareholders' equity:
Common stock, par value	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized	350,000,000	350,000,000	350,000,000
Common stock, shares issued	308,736,705	286,449,511	268,174,642
Common stock, shares outstanding	308,736,705	286,449,511	268,174,642