Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017		Jun. 30, 2016
Operating activities:
Net income	$ 547,755		$ 513,168
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, equipment and intangibles	114,959		106,430
Amortization of debt discount and issuance costs	1,344		1,173
Deferred income taxes	8,049		(6,811)
Share-based compensation programs	10,353		9,853
Other	6,037		2,655
Changes in operating assets and liabilities:
Accounts receivable	(10,797)		(28,837)
Inventory	(179,866)		(110,015)
Accounts payable	155,124		306,410
Income taxes payable	58,173		25,170
Other	(624)		9,538	[1]
Net cash provided by operating activities	710,507		828,734	[1]
Investing activities:
Purchases of property and equipment	(227,506)		(220,416)
Proceeds from sale of property and equipment	752		1,971
Payments received on notes receivable	0		1,047
Other	(1,967)		0
Net cash used in investing activities	(228,721)		(217,398)
Financing activities:
Proceeds from borrowings on revolving credit facility	1,782,000		0
Payments on revolving credit facility	(1,066,000)		0
Proceeds from the issuance of long-term debt	0		499,160
Payments of debt issuance costs	(1,827)		(3,784)
Repurchases of common stock	(1,342,591)		(856,845)
Net proceeds from issuance of common stock	26,718		32,296
Other	(156)		(205)	[1]
Net cash used in financing activities	(601,856)		(329,378)	[1]
Net (decrease) increase in cash and cash equivalents	(120,070)		281,958
Cash and cash equivalents at beginning of the period	146,598	[2]	116,301
Cash and cash equivalents at end of the period	26,528		398,259
Supplemental disclosures of cash flow information:
Income taxes paid	203,780		279,099
Interest paid, net of capitalized interest	$ 37,151		$ 27,174

[1] Certain prior period amounts have been reclassified to conform to current period presentation. See Note 9 “Recent Accounting Pronouncements” to the condensed consolidated financial statements in this report for more information.

[2] The balance sheet at December 31, 2016, has been derived from the audited consolidated financial statements at that date, but does not include all of the information and footnotes required by United States generally accepted accounting principles for complete financial statements.