Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
CURRENT ASSETS:
Cash and cash equivalents	$ 43,047	$ 37,437
Marketable securities	55,043	55,586
Accounts receivable, net	50,529	76,443
Inventories:
Finished goods	37,805	33,851
Work in process	50,051	40,340
Raw materials	9,021	9,173
Total inventory	96,877	83,364
Deferred tax assets	8,906	8,906
Other current assets	15,853	9,018
Total current assets	270,255	270,754
PROPERTY, PLANT AND EQUIPMENT	129,164	123,418
Less allowance for depreciation	63,645	61,553
PROPERTY, PLANT AND EQUIPMENT, NET	65,519	61,865
GOODWILL & OTHER INTANGIBLES	17,555	17,722
NOTE RECEIVABLE	3,602	3,571
Total assets	356,931	353,912
CURRENT LIABILITIES:
Accounts payable	34,327	39,077
Federal and state income taxes	2,678	1,642
Accrued liabilities	14,904	15,254
Total current liabilities	51,909	55,973
DEFERRED INCOME TAXES	7,372	7,368
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY
Common stock, $1 par value: Authorized: 12,000,000 Issued: 7,440,518	7,441	7,441
Paid-in capital	4,620	4,472
Retained earnings	302,497	295,643
Accumulated other comprehensive income	61	53
Stockholders' Equity before Treasury Stock	314,619	307,609
Treasury stock, at cost	16,969	17,038
Total stockholders' equity	297,650	290,571
Total liabilities and stockholders' equity	$ 356,931	$ 353,912