Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Sales	$ 2,080,201	$ 1,876,872	$ 6,017,622	$ 5,451,903
Cost of goods sold, including warehouse and distribution expenses	990,947	908,671	2,882,618	2,655,109
Gross profit	1,089,254	968,201	3,135,004	2,796,794
Selling, general and administrative expenses	673,994	624,433	1,983,603	1,829,432
Operating income	415,260	343,768	1,151,401	967,362
Other income (expense):
Interest expense	(14,296)	(12,983)	(43,017)	(39,211)
Interest income	551	551	1,708	1,688
Other, net	(647)	982	648	2,237
Total other expense	(14,392)	(11,450)	(40,661)	(35,286)
Income before income taxes	400,868	332,318	1,110,740	932,076
Provision for income taxes	134,600	115,321	398,100	335,572
Net income	$ 266,268	$ 216,997	$ 712,640	$ 596,504
Earnings per share-basic:
Earnings per share - basic	$ 2.68	$ 2.10	$ 7.09	$ 5.67
Weighted-average common shares outstanding - basic	99,270	103,498	100,468	105,146
Earnings per share-assuming dilution:
Earnings per share - assuming dilution	$ 2.64	$ 2.06	$ 6.98	$ 5.58
Weighted-average common shares outstanding - assuming dilution	100,770	105,222	102,041	106,945