CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $) In Thousands, except Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) [Abstract]
Net Sales	$ 79,173	$ 77,732	$ 150,576	$ 133,801
Costs and expenses:
Cost of sales	65,368	61,570	122,500	108,727
Selling, general and administrative	10,421	10,291	20,478	19,480
Litigation charges	3,224	0	3,224	0
Total Costs and Expenses	79,013	71,861	146,202	128,207
Income from operations	160	5,871	4,374	5,594
Gain on sale of investment	119	0	119	0
Interest income and other, net	93	116	161	238
Earnings before provision for income taxes	372	5,987	4,654	5,832
Provision for income taxes	946	1,197	1,984	1,162
Net (loss) earnings	$ (574)	$ 4,790	$ 2,670	$ 4,670
Class A [Member]
(Loss) earnings per share:
(Loss) earnings per share - basic and diluted	$ (0.05)	$ 0.39	$ 0.21	$ 0.37
Weighted-average shares outstanding:
Weighted-average shares outstanding - basic and diluted	2,174,912	2,174,912	2,174,912	2,174,912
Dividends paid per share:
Dividends paid per share -common share	$ 0.06	$ 0.06	$ 0.12	$ 0.12
Class B [Member]
(Loss) earnings per share:
(Loss) earnings per share - basic and diluted	$ (0.05)	$ 0.42	$ 0.23	$ 0.41
Weighted-average shares outstanding:
Weighted-average shares outstanding - basic and diluted	9,582,610	9,495,824	9,554,354	9,480,134
Dividends paid per share:
Dividends paid per share -common share	$ 0.07	$ 0.07	$ 0.14	$ 0.14

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