Consolidated Statements of Income (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
Income Statement [Abstract]
NET SALES	$ 145,376	$ 100,415	$ 295,478	$ 210,453
COST OF GOODS SOLD	92,419	74,570	184,431	159,242
Gross profit	52,957	25,845	111,047	51,211
OPERATING EXPENSES
Selling, general and administrative	19,456	15,632	38,294	29,529
Acquisition related charge (credit)	838	(31)	1,422	(119)
Research and development	3,214	3,174	6,281	6,118
Restructuring - plant closure and severance	0	0	0	7
Operating Expenses, Total	23,508	18,775	45,997	35,535
INCOME FROM OPERATIONS	29,449	7,070	65,050	15,676
OTHER INCOME (EXPENSE):
Interest income	877	728	1,675	1,627
Interest expense	(1,669)	(1,609)	(3,117)	(3,195)
Gain (loss) on auction rate securities	0	949	0	(978)
Miscellaneous	677	881	590	1,410
Other Income (Expense), Total	(115)	949	(852)	(1,136)
INCOME BEFORE PROVISION FOR INCOME TAXES	29,334	8,019	64,198	14,540
PROVISION FOR INCOME TAXES	10,203	1,456	21,472	2,987
NET INCOME	$ 19,131	$ 6,563	$ 42,726	$ 11,553
BASIC INCOME PER SHARE (in dollars per share)	$ 0.77	$ 0.26	$ 1.72	$ 0.45
DILUTED INCOME PER SHARE (in dollars per share)	$ 0.76	$ 0.26	$ 1.70	$ 0.45
WEIGHTED AVERAGE SHARES OUTSTANDING:
BASIC (in shares)	24,898	25,431	24,869	25,421
DILUTED (in shares)	25,224	25,597	25,172	25,576