CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS (UNAUDITED) (USD $) In Thousands, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS
Net sales	$ 515,996	$ 465,813	$ 1,492,751	$ 1,369,753
Cost of sales	345,359	310,096	1,004,188	921,669
Gross profit	170,637	155,717	488,563	448,084
Research and development expenses	17,705	13,218	46,431	40,894
Selling expenses	30,918	27,560	90,077	83,900
General and administrative expenses	71,868	66,853	208,537	200,692
Operating income	50,146	48,086	143,518	122,598
Interest expense	(5,033)	(5,815)	(15,121)	(17,182)
Other (expense) income, net	(35)	86	50	622
Earnings before income taxes	45,078	42,357	128,447	106,038
Provision for income taxes	10,718	14,573	37,775	36,021
Net earnings	$ 34,360	$ 27,784	$ 90,672	$ 70,017
Earnings Per Share [Abstract]
Basic earnings per share	$ 0.74	$ 0.61	$ 1.96	$ 1.53
Diluted earnings per share	$ 0.73	$ 0.60	$ 1.93	$ 1.51
Dividends per share	$ 0.08	$ 0.08	$ 0.24	$ 0.24
Weighted average shares outstanding:
Basic weighted-average shares outstanding	46,466	45,898	46,328	45,765
Diluted weighted-average shares outstanding	46,936	46,276	46,978	46,253