Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Sales	$ 620,614	$ 717,229	$ 605,674
Cost of sales	303,971	302,911	246,811
Gross Profit	316,643	414,318	358,863
Selling, general and administrative expenses	134,523	124,879	114,699
Research and development expenses	125,951	100,301	90,300
Operating Income	56,169	189,138	153,864
Interest and dividend income	7,657	7,642	6,557
Interest expense	(2,347)	(2,398)	(2,436)
Net realized investment gain	9,550	12,454	11,008
Other income (expense), net	183	(694)	(804)
Gain on bargain purchase of a business	1,753
Income before provision for income taxes	72,965	206,142	168,189
Provision for income taxes	(25,702)	(67,565)	(54,200)
Net Income	$ 47,263	$ 138,577	$ 113,989
Weighted average shares outstanding - basic	63,259	64,145	62,490
Weighted average shares outstanding - diluted	63,774	65,416	63,879
Earnings per common share - basic	$ 0.75	$ 2.16	$ 1.82
Earnings per common share - diluted	$ 0.74	$ 2.12	$ 1.78