Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Net sales:
Products	$ 650,883	$ 479,437	$ 439,125
Products - related party	3,716	343	578
Service and components	171,329	154,021	137,361
Service and components - related party	498	421	280
Total net sales	826,426	634,222	577,344
Cost of sales:
Products	344,575	262,571	252,307
Service and components	114,485	102,387	95,533
Total cost of sales	459,060	364,958	347,840
Gross profit	367,366	269,264	229,504
Operating expenses:
Research and development	78,318	66,274	67,698
Selling, general and administrative	158,782	136,465	126,728
Restructuring, reorganization, relocation and severance	3,215	11,067	3,456
Total operating expenses	240,315	213,806	197,882
Operating income	127,051	55,458	31,622
Other (expense) income:
Interest income	2,361	2,632	2,880
Interest expense	(4,037)	(4,504)	(5,441)
Other, net	(2,510)	(1,364)	(1,400)
Total other expense, net	(4,186)	(3,236)	(3,961)
Income before income taxes	122,865	52,222	27,661
Income tax expense (benefit)	19,228	(1,326)	5,017
Net income	$ 103,637	$ 53,548	$ 22,644
Basic net income per share	$ 2.70	$ 1.41	$ 0.60
Diluted net income per share	$ 2.51	$ 1.34	$ 0.60
Shares used in per share calculations:
Basic	38,384	38,083	37,537
Diluted	42,047	41,737	37,905