CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Dec. 31, 2011	Dec. 31, 2010
Stockholders' equity:
Convertible preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Convertible preferred stock, shares authorized (in shares)	5,000	5,000
Convertible preferred stock, shares issued (in shares)	0	0
Convertible preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	80,000	80,000
Common stock, shares issued (in shares)	17,288	17,222
Common stock, shares outstanding (in shares)	17,288	17,222