Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating activities:
Net income	$ 585,746	$ 507,673	$ 419,373
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, equipment and intangibles	177,106	165,880	161,442
Amortization of debt premium, discount and issuance costs	1,788	1,797	7,852
Write-off of asset-based revolving credit facility debt issuance costs	0	21,626	0
Excess tax benefit from stock options exercised	(38,631)	(22,985)	(18,587)
Deferred income taxes	8,162	54,120	99,257
Gain on settlement of note receivable	0	0	(11,639)
Share-based compensation programs	22,026	20,579	16,973
Other	7,464	8,292	6,893
Changes in operating assets and liabilities:
Accounts receivable	4,404	(21,219)	(21,748)
Inventory	(276,904)	37,740	(110,271)
Accounts payable	645,706	383,632	82,574
Income taxes payable	71,346	(8,625)	15,346
Accrued payroll	7,655	(269)	9,939
Accrued benefits and withholdings	5,464	1,500	8,930
Other	30,223	(30,750)	37,353
Net cash provided by operating activities	1,251,555	1,118,991	703,687
Investing activities:
Purchases of property and equipment	(300,719)	(328,319)	(365,419)
Proceeds from sale of property and equipment	3,044	2,715	2,124
Payments received on notes receivable	4,157	5,435	17,364
Other	(23,889)	516	(5,346)
Net cash used in investing activities	(317,407)	(319,653)	(351,277)
Financing activities:
Proceeds from borrowings on asset-based revolving credit facility	0	42,400	548,700
Payments on asset-based revolving credit facility	0	(398,400)	(871,500)
Proceeds from the issuance of long-term debt	298,881	795,963	0
Payment of debt issuance costs	(2,376)	(9,942)	0
Principal payments on debt and capital leases	(935)	(1,443)	(108,527)
Repurchases of common stock	(1,445,287)	(976,632)	0
Excess tax benefit from stock options exercised	38,631	22,985	18,587
Net proceeds from issuance of common stock	63,514	57,562	63,116
Net cash used in financing activities	(1,047,572)	(467,507)	(349,624)
Net increase (decrease) in cash and cash equivalents	(113,424)	331,831	2,786
Cash and cash equivalents at beginning of period	361,552	29,721	26,935
Cash and cash equivalents at end of period	248,128	361,552	29,721
Supplemental disclosures of cash flow information:
Income taxes paid	274,637	252,769	154,146
Interest paid, net of capitalized interest	$ 34,655	$ 13,350	$ 31,211