Condensed Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Condensed Balance Sheets [Abstract]
Accumulated amortization on license agreements	$ 1,260	$ 1,211
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	15,000	15,000
Preferred stock, issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000	300,000
Common stock, shares issued	17,548	15,177
Common stock, shares outstanding	17,548	15,177