Condensed Consolidated Statements of Income and Comprehensive Income (unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Net sales	$ 3,736,051us-gaap_SalesRevenueGoodsNet	$ 3,624,897us-gaap_SalesRevenueGoodsNet
Cost of goods sold	2,623,232us-gaap_CostOfGoodsSold	2,540,267us-gaap_CostOfGoodsSold
Gross profit	1,112,819us-gaap_GrossProfit	1,084,630us-gaap_GrossProfit
Operating expenses:
Selling, administrative, and other expenses	825,554	803,802
Depreciation and amortization	35,884us-gaap_DepreciationAndAmortization	36,856us-gaap_DepreciationAndAmortization
Total operating expenses	861,438us-gaap_OperatingExpenses	840,658us-gaap_OperatingExpenses
Income before income taxes	251,381	243,972
Income taxes	90,371us-gaap_IncomeTaxExpenseBenefit	86,488us-gaap_IncomeTaxExpenseBenefit
Net income	161,010us-gaap_ProfitLoss	157,484us-gaap_ProfitLoss
Basic net income per common share	$ 1.05us-gaap_EarningsPerShareBasic	$ 1.02us-gaap_EarningsPerShareBasic
Diluted net income per common share	$ 1.05us-gaap_EarningsPerShareDiluted	$ 1.02us-gaap_EarningsPerShareDiluted
Dividends declared per common share	$ 0.615	$ 0.575
Weighted average common shares outstanding	152,656	153,729
Dilutive effect of stock options and non-vested restricted stock awards	918	1,067
Weighted average common shares outstanding - assuming dilution	153,574	154,796
Comprehensive income	$ 53,539	$ 161,377

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770