Condensed Consolidated Statements of Income and Comprehensive Income (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Consolidated Statements of Income [Abstract]
Net sales	$ 3,181,288	$ 2,974,198
Cost of goods sold	2,262,177	2,125,404
Gross profit	919,111	848,794
Operating expenses:
Selling, administrative and other expenses	667,958	634,269
Depreciation and amortization	22,985	22,545
Total operating expenses	690,943	656,814
Income before income taxes	228,168	191,980
Income taxes	81,913	65,465
Net income	146,255	126,515
Basic net income per common share	$ 0.94	$ 0.80
Diluted net income per common share	$ 0.93	$ 0.80
Dividends declared per common share	$ 0.495	$ 0.45
Weighted average common shares outstanding	155,810	157,633
Dilutive effect of stock options and non-vested restricted stock awards	1,139	1,023
Weighted average common shares outstanding - assuming dilution	156,949	158,656
Comprehensive income	$ 174,774	$ 154,838