Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Sales	$ 2,482,717	$ 2,339,830	$ 7,221,471	$ 6,786,918
Cost of goods sold, including warehouse and distribution expenses	1,166,962	1,109,536	3,415,820	3,225,415
Gross profit	1,315,755	1,230,294	3,805,651	3,561,503
Selling, general and administrative expenses	830,607	768,331	2,418,507	2,238,938
Operating income	485,148	461,963	1,387,144	1,322,565
Other income (expense):
Interest expense	(31,582)	(24,324)	(90,661)	(64,555)
Interest income	669	592	1,838	1,768
Other, net	1,416	1,299	2,609	1,302
Total other expense	(29,497)	(22,433)	(86,214)	(61,485)
Income before income taxes	455,651	439,530	1,300,930	1,261,080
Provision for income taxes	89,500	155,796	276,800	429,591
Net income	$ 366,151	$ 283,734	$ 1,024,130	$ 831,489
Earnings per share-basic:
Earnings per share - basic	$ 4.54	$ 3.26	$ 12.50	$ 9.28
Weighted-average common shares outstanding - basic	80,593	86,947	81,939	89,641
Earnings per share-assuming dilution:
Earnings per share - assuming dilution	$ 4.50	$ 3.22	$ 12.36	$ 9.15
Weighted-average common shares outstanding - assuming dilution	81,410	88,025	82,841	90,869