Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Current assets:
Allowance for doubtful accounts, accounts receivable	$ 1,185	$ 1,026
Stockholders' equity:
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	43,660,157	42,901,926
Common stock, shares outstanding	37,802,279	37,044,048