CONSOLIDATED BALANCE SHEETS (Parenthetical) (Unaudited) (USD $)	Sep. 30, 2011	Dec. 31, 2010
Stockholders' equity:
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, authorized (in shares)	10,000,000	10,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	40,000,000	40,000,000
Common stock, issued (in shares)	17,751,327	17,705,980
Common stock, outstanding (in shares)	17,608,248	17,562,901