Condensed Consolidated Statements Of Income (USD $) In Thousands, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Condensed Consolidated Statements Of Income [Abstract]
Net sales	$ 140,973	$ 113,608	$ 431,091	$ 348,321
Cost of goods sold	(132,129)	(108,100)	(394,243)	(317,584)
Gross margin	8,844	5,508	36,848	30,737
Other operating income (expense):
Selling expense	(1,775)	(1,448)	(5,573)	(4,949)
General and administrative expense	(3,881)	(2,434)	(11,605)	(10,315)
Defined benefit pension credit	4,750	1,211	14,250	3,632
Other postretirement benefit credit	1,299	1,342	3,898	4,029
Total other operating income (expense)	393	(1,329)	970	(7,603)
Operating income	9,237	4,179	37,818	23,134
Nonoperating income (expense):
Interest expense	(319)	(502)	(922)	(1,567)
Other income, net	113	125	661	272
Total nonoperating expense	(206)	(377)	(261)	(1,295)
Income before income taxes	9,031	3,802	37,557	21,839
Provision for income taxes	(3,595)	(1,483)	(15,442)	(8,396)
Net income	$ 5,436	$ 2,319	$ 22,115	$ 13,443
Basic and diluted income per share	$ 0.45	$ 0.19	$ 1.83	$ 1.11
Basic and diluted weighted average shares outstanding	12,102	12,102	12,102	12,102