Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Consolidated Balance Sheets [Abstract]
Allowance for doubtful accounts and customer credits	$ 53,841	$ 53,311
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	18,084,877	18,078,261
Common stock, shares outstanding	18,084,877	18,078,261