Condensed Consolidated Balance Sheets (Parenthetical) (unaudited) (USD $)
In Thousands, except Share data, unless otherwise specified
Mar. 31, 2013
Dec. 31, 2012
Condensed Consolidated Balance Sheets [Abstract]    
Allowance for doubtful accounts $ 3,318 $ 2,617
Common Stock, par value $ 0.001 $ 0.001
Common Stock, shares authorized 120,000,000 120,000,000
Common Stock, shares issued 30,339,098 30,106,933
Common Stock, shares outstanding 30,339,098 30,106,933