8. Net Loss per Common Share (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Net Loss Per Common Share Details
Basic and diluted weighted average common stock shares outstanding	70,035,710	69,679,854
Common stock options	19,873,747	18,766,977
Common stock purchase warrants	$ 7,718,750	$ 6,218,750