CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Net sales
Product sales	$ 402,918	$ 445,687
Service sales	100,589	100,512
Total net sales	503,507	546,199
Cost of sales
Cost of product sales	264,735	293,009
Cost of service sales	66,869	62,094
Total cost of sales	331,604	355,103
Gross profit	171,903	191,096
Research and development expenses	15,160	15,262
Selling expenses	29,626	31,088
General and administrative expenses	69,854	71,911
Operating income	57,263	72,835
Interest expense	(9,933)	(8,996)
Other income, net	(234)	(481)
Earnings before income taxes	47,564	64,320
Provision for income taxes	(14,745)	(21,097)
Earnings from continuing operations	32,819	43,223
Loss from discontinued operations, net of taxes	0	(27,232)
Net earnings	$ 32,819	$ 15,991
Earnings Per Share, Basic [Abstract]
Earnings from continuing operations	$ 0.74	$ 0.91
Loss from discontinued operations	0.00	(0.57)
Basic earnings per share (usd per share)	0.74	0.34
Earnings Per Share, Diluted [Abstract]
Earnings from continuing operations	0.73	0.89
Loss from discontinued operations	0.00	(0.56)
Diluted earnings per share (usd per share)	0.73	0.33
Dividends per share	$ 0.13	$ 0.13
Weighted average shares outstanding:
Basic (shares)	44,578	47,724
Diluted (shares)	45,240	48,732