Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Dec. 31, 2010
Current assets:
Allowance for accounts receivable	$ 2,579	$ 2,582
Stockholders' equity:
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, share issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock , shares authorized	40,000,000	40,000,000
Common stock, shares issued	26,442,752	26,366,752
Treasury stock, shares	3,150,277	3,150,277