Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Accounts receivable, reserve for doubtful accounts	$ 2,402	$ 3,393
Property, plant and equipment, accumulated depreciation	$ 119,977	$ 117,359
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	60,000,000	60,000,000
Common stock, shares issued	28,601,861	28,463,479
Common stock, shares outstanding	28,601,861	28,463,479
Treasury stock, shares	590,154	590,154