Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Sales	$ 7,966,674	$ 7,216,081	$ 6,649,237
Cost of goods sold, including warehouse and distribution expenses	3,804,031	3,507,180	3,280,236
Gross profit	4,162,643	3,708,901	3,369,001
Selling, general and administrative expenses	2,648,622	2,438,527	2,265,516
Operating income	1,514,021	1,270,374	1,103,485
Other income (expense):
Interest expense	(57,129)	(53,290)	(49,074)
Interest income	2,340	2,301	1,992
Other, net	1,134	2,797	2,539
Total other expense	(53,655)	(48,192)	(44,543)
Income before income taxes	1,460,366	1,222,182	1,058,942
Provision for income taxes	529,150	444,000	388,650
Net income	$ 931,216	$ 778,182	$ 670,292
Earnings per share-basic:
Earnings per share - basic	$ 9.32	$ 7.46	$ 6.14
Weighted-average common shares outstanding - basic	99,965	104,262	109,244
Earnings per share-assuming dilution:
Earnings per share - assuming dilution	$ 9.17	$ 7.34	$ 6.03
Weighted-average common shares outstanding - assuming dilution	101,514	106,041	111,101