Condensed Consolidated Statements Of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenues:
Products	$ 160,485	$ 149,706
Services	32,670	27,418
Total revenues	193,155	177,124
Cost and expenses:
Products	96,673	92,123
Services	19,655	14,927
Total cost of sales	116,328	107,050
Selling, general and administrative	15,629	20,432
Engineering and product development	9,021	9,610
Total costs and expenses	140,978	137,092
Operating income	52,177	40,032
Interest income	116	103
Interest expense	(14)	(5)
Income before income taxes	52,279	40,130
Income tax provision	12,437	11,333
Net income	$ 39,842	$ 28,797
Earnings per common share:
Basic	$ 0.98	$ 0.72
Diluted	$ 0.98	$ 0.71
Weighted average common shares outstanding:
Basic	40,529	40,184
Diluted	40,713	40,411