Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Convertible debt, derivative liability	$ 3,680	$ 5,914
Convertible debt, unamortized debt discount	4,229	4,610
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	70,203,216	68,744,534
Common stock, shares outstanding	70,203,216	68,744,534
Convertible debt
Convertible debt, derivative liability	3,680	5,914
Convertible debt, unamortized debt discount	$ 4,229	$ 4,610