Condensed Consolidated Statements of Income and Comprehensive Income (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Net sales	$ 3,718,267	$ 3,736,051
Cost of goods sold	2,613,796	2,623,232
Gross profit	1,104,471	1,112,819
Operating expenses:
Selling, administrative, and other expenses	823,172	825,554
Depreciation and amortization	34,654	35,884
Total operating expenses	857,826	861,438
Income before income taxes	246,645	251,381
Income taxes	88,620	90,371
Net income	$ 158,025	$ 161,010
Basic net income per common share	$ 1.06	$ 1.05
Diluted net income per common share	1.05	1.05
Dividends declared per common share	$ 0.6575	$ 0.6150
Weighted average common shares outstanding	149,593	152,656
Dilutive effect of stock options and non-vested restricted stock awards	749	918
Weighted average common shares outstanding - assuming dilution	150,342	153,574
Comprehensive income	$ 226,124	$ 53,539