Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Condensed Consolidated Balance Sheets [Abstract]
Receivables, allowance for doubtful accounts	$ 1,537	$ 1,585
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	75,000	75,000
Common stock, shares issued	38,973	38,193
Common stock, shares outstanding	38,973	38,193
Preferred stock, shares authorized	500	500
Preferred stock, shares issued
Preferred stock, shares outstanding