CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS (UNAUDITED) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Net sales
Product sales	$ 526,354	$ 486,584
Service sales	115,058	106,103
Total net sales	641,412	592,687
Cost of sales
Cost of product sales	363,654	339,626
Cost of service sales	75,606	69,354
Total cost of sales	439,260	408,980
Gross profit	202,152	183,707
Research and development expenses	18,349	17,608
Selling expenses	39,638	36,796
General and administrative expenses	85,064	91,277
Operating income	59,101	38,026
Interest expense	(9,054)	(8,659)
Other income, net	65	474
Earnings before income taxes	50,112	29,841
Provision for income taxes	14,948	8,898
Net earnings	$ 35,164	$ 20,943
Earnings Per Share [Abstract]
Basic earnings per share (usd per share)	$ 0.73	$ 0.45
Diluted earnings per share (usd per share)	$ 0.72	$ 0.44
Dividends per share	$ 0.13	$ 0.09
Weighted average shares outstanding:
Basic (shares)	47,982	46,615
Diluted (shares)	49,130	47,483