Quarterly Results of Operations (Unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 605,997	$ 624,246	$ 642,099	$ 622,231	$ 614,094	$ 622,888	$ 634,360	$ 612,324	$ 2,494,573	$ 2,483,666	$ 2,287,312
Gross profit	266,885	281,978	292,337	283,834	273,643	280,233	287,367	276,652	1,125,034	1,117,895	1,026,678
Operating income	134,173	141,765	155,283	147,782	139,441	145,133	147,831	136,683	579,003	569,088	502,556
Net income	$ 96,850	$ 105,194	$ 113,209	$ 110,268	$ 98,137	$ 106,352	$ 107,126	$ 98,958	$ 425,521	$ 410,573	$ 337,257
Basic EPS (in dollar per share)	$ 1.28	$ 1.39	$ 1.50	$ 1.46	$ 1.29	$ 1.39	$ 1.40	$ 1.29	$ 5.62	$ 5.36	$ 4.41
Diluted EPS (in dollar per share)	$ 1.26	$ 1.37	$ 1.48	$ 1.44	$ 1.27	$ 1.37	$ 1.38	$ 1.27	$ 5.56	$ 5.29	$ 4.36
Basic weighted average shares outstanding (in shares)	75,779	75,698	75,460	75,442	76,128	76,562	76,539	76,419	75,594	76,412	76,232
Diluted weighted average shares outstanding (in shares)	76,570	76,577	76,387	76,284	77,100	77,709	77,704	77,739	76,454	77,563	77,333