CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Operating activities:
Net income	$ 152,608	$ 397,906	$ 554,181	$ 985,953
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	79,470	81,383	240,555	236,638
Equity-based compensation	8,841	7,978	33,229	28,860
Deferred income taxes	11,311	23,899	34,952	45,437
Other adjustments	(1,116)	312	(952)	197
Changes in certain assets and liabilities:
Accounts receivable	85,633	(48,024)	95,195	(330,307)
Inventories	35,479	(69,885)	139,889	(240,908)
Other assets	39	(6,429)	7,632	(7,164)
Accounts payable	1,111	(14,883)	(54,167)	100,368
Income taxes receivable/payable	6,293	(31,127)	19,715	55,414
Accrued expenses	64,533	79,310	(83,001)	49,920
Net cash provided by operating activities	444,202	420,440	987,228	924,408
Investing activities:
Purchases of property, plant and equipment	(154,131)	(70,668)	(293,687)	(176,477)
Purchases of short-term investments	(34,884)	(35,000)	(134,026)	(125,000)
Proceeds from maturities of short-term investments	79,508	10,000	293,279	10,000
Acquisition of business, net of cash and restricted cash acquired	(3,694)	(37,589)	(97,106)	(433,998)
Other investing activities	2,746	576	4,023	1,462
Net cash used in investing activities	(110,455)	(132,681)	(227,517)	(724,013)
Financing activities:
Issuance of current and long-term debt	128,230	110,041	374,686	327,670
Repayment of current and long-term debt	(119,988)	(115,039)	(369,134)	(346,162)
Dividends paid	(52,751)	(44,081)	(148,493)	(125,146)
Purchases of treasury stock	(114,950)	(74,965)	(292,394)	(193,379)
Other financing activities	(1,527)		(7,259)	(8,324)
Net cash used in financing activities	(160,986)	(124,044)	(442,594)	(345,341)
Increase (decrease) in cash, cash equivalents, and restricted cash	172,761	163,715	317,117	(144,946)
Cash, cash equivalents, and restricted cash at beginning of period	978,779	726,424	834,423	1,035,085
Cash, cash equivalents, and restricted cash at end of period	1,151,540	890,139	1,151,540	890,139
Supplemental disclosure information:
Cash paid for interest	9,115	8,643	71,702	70,498
Cash paid for income taxes, net	$ 29,794	$ 119,802	$ 116,149	$ 198,752