Condensed Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Statement [Abstract]
Sales	$ 1,847,088	$ 1,714,969	$ 3,575,031	$ 3,299,978
Cost of goods sold, including warehouse and distribution expenses	896,211	843,094	1,746,438	1,629,440
Gross profit	950,877	871,875	1,828,593	1,670,538
Selling, general and administrative expenses	614,403	575,614	1,204,999	1,123,193
Operating income	336,474	296,261	623,594	547,345
Other income (expense):
Interest expense	(12,819)	(11,467)	(26,228)	(22,867)
Interest income	506	469	1,137	946
Other, net	637	864	1,255	1,332
Total other expense	(11,676)	(10,134)	(23,836)	(20,589)
Income before income taxes	324,798	286,127	599,758	526,756
Provision for income taxes	119,151	109,000	220,251	195,300
Net income	$ 205,647	$ 177,127	$ 379,507	$ 331,456
Earnings per share-basic:
Earnings per share - basic	$ 1.94	$ 1.61	$ 3.58	$ 2.99
Weighted-average common shares outstanding - basic	105,772	110,278	105,982	110,914
Earnings per share-assuming dilution:
Earnings per share - assuming dilution	$ 1.91	$ 1.58	$ 3.52	$ 2.94
Weighted-average common shares outstanding - assuming dilution	107,556	112,079	107,817	112,736