CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 46,055	$ 30,905
Short-term investment		12,015
Accounts receivable, net	57,046	47,258
Inventories	33,293	33,846
Prepaid expenses and other current assets, net	8,607	6,796
Total current assets	145,001	130,820
Property, plant and equipment, at cost	242,411	240,157
Accumulated depreciation	(164,833)	(161,218)
Net, property, plant and equipment	77,578	78,939
Goodwill	18,018	18,059
Other intangible assets	4,058	4,537
Other assets, net	2,375	2,830
Total assets	247,030	235,185
Current liabilities:
Current portion of long-term debt	843	1,035
Accounts payable	31,887	28,163
Accrued payroll and other compensation	9,828	9,031
Accrued taxes	3,027	2,532
Other accrued liabilities	4,560	4,038
Total current liabilities	50,145	44,799
Long-term debt	1,955	2,261
Deferred tax liabilities	5,291	5,240
Benefit plan liabilities	20,304	21,269
Other long-term liabilities	1,020	764
Commitments and Contingencies (Note 13)
Stockholders' equity:
Preferred stock
Common stock	2,373	2,365
Capital in excess of par value	57,256	56,214
Retained earnings	194,795	184,291
Accumulated other comprehensive loss	(17,997)	(16,618)
Treasury stock, at cost	(68,112)	(65,400)
Total stockholders' equity	168,315	160,852
Total liabilities and stockholders' equity	$ 247,030	$ 235,185