Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating activities:
Net income	$ 1,391,042	$ 1,324,487	$ 1,133,804
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, equipment and intangibles	270,875	258,937	233,845
Amortization of debt discount and issuance costs	3,916	3,470	2,871
Deferred income taxes	21,158	20,160	(4,593)
Share-based compensation programs	21,921	20,176	19,401
Other	7,529	9,895	11,790
Changes in operating assets and liabilities:
Accounts receivable	(15,577)	18,138	(27,742)
Inventory	(239,912)	(163,367)	(231,802)
Accounts payable	213,423	177,676	253,265
Income taxes payable	(20,139)	22,903	14,220
Accrued payroll	14,296	9,373	5,430
Accrued benefits and withholdings	16,868	28,022	3,042
Other	23,079	(2,315)	(9,844)
Net cash provided by operating activities	1,708,479	1,727,555	1,403,687
Investing activities:
Purchases of property and equipment	(628,057)	(504,268)	(465,940)
Proceeds from sale of property and equipment	7,118	4,784	4,464
Investment in tax credit equity investments	(33,781)	0	0
Other, including acquisitions, net of cash acquired	(142,026)	(34,818)	(2,747)
Net cash used in investing activities	(796,746)	(534,302)	(464,223)
Financing activities:
Proceeds from borrowings on revolving credit facility	2,708,000	2,414,000	3,101,000
Payments on revolving credit facility	(2,734,000)	(2,473,000)	(2,755,000)
Proceeds from the issuance of long-term debt	499,955	498,660	748,800
Payment of debt issuance costs	(3,990)	(3,923)	(7,590)
Repurchases of common stock	(1,432,791)	(1,714,013)	(2,172,530)
Net proceeds from issuance of common stock	60,206	72,146	45,762
Other	(191)	(2,156)	(156)
Net cash used in financing activities	(902,811)	(1,208,286)	(1,039,714)
Effect of exchange rate changes on cash	169	0	0
Net increase (decrease) in cash and cash equivalents	9,091	(15,033)	(100,250)
Cash and cash equivalents at beginning of the year	31,315	46,348	146,598
Cash and cash equivalents at end of the year	40,406	31,315	46,348
Supplemental disclosures of cash flow information:
Income taxes paid	394,931	311,376	496,728
Interest paid, net of capitalized interest	$ 134,634	$ 117,938	$ 77,766