CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS (UNAUDITED) (USD $) In Thousands, except Per Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS
Net sales	$ 514,905	$ 462,165	$ 976,755	$ 903,940
Cost of sales	345,948	307,782	658,829	611,573
Gross profit	168,957	154,383	317,926	292,367
Research and development expenses	15,129	13,838	28,726	27,676
Selling expenses	29,936	28,520	59,159	56,340
General and administrative expenses	72,203	68,597	136,669	133,839
Operating income	51,689	43,428	93,372	74,512
Interest expense	(4,967)	(5,700)	(10,088)	(11,367)
Other income, net	29	384	85	536
Earnings before income taxes	46,751	38,112	83,369	63,681
Provision for income taxes	14,955	12,214	27,057	21,448
Net earnings	$ 31,796	$ 25,898	$ 56,312	$ 42,233
Earnings Per Share [Abstract]
Basic earnings per share	$ 0.69	$ 0.57	$ 1.22	$ 0.92
Diluted earnings per share	$ 0.68	$ 0.56	$ 1.20	$ 0.91
Dividends per share	$ 0.08	$ 0.08	$ 0.16	$ 0.16
Weighted average shares outstanding:
Basic weighted-average shares outstanding	46,311	45,743	46,250	45,691
Diluted weighted-average shares outstanding	47,015	46,311	46,991	46,233

Aggregate dividends declared during the period for each share of common stock outstanding.

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