CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Net sales	$ 2,287,312	$ 2,113,043	$ 2,020,668
Cost of sales	1,260,634	1,182,276	1,116,353
Gross profit	1,026,678	930,767	904,315
Selling, general and administrative expenses	524,940	492,398	474,156
Loss (gain) on sale of businesses - net	(9,273)	22,298	(18,070)
Restructuring expenses	8,455	3,674	11,239
Operating income	502,556	412,397	436,990
Other (income) expense - net	2,394	(1,731)	3,009
Interest expense	44,889	45,616	41,636
Income before income taxes	455,273	368,512	392,345
Provision for income taxes	118,016	97,403	109,538
Net income	$ 337,257	$ 271,109	$ 282,807
Earnings per common share:
Basic earnings per common share (in dollar per share)	$ 4.41	$ 3.57	$ 3.65
Diluted earnings per common share (in dollar per share)	$ 4.36	$ 3.53	$ 3.62
Share data:
Basic weighted average common shares outstanding (in shares)	76,232	75,803	77,126
Diluted weighted average common shares outstanding (in shares)	77,333	76,758	77,972