CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Operating activities:
Net income	$ 196,746	$ 362,572	$ 401,573	$ 588,047
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	80,911	79,120	161,085	155,255
Equity-based compensation	9,080	8,041	24,388	20,882
Deferred income taxes	11,550	11,993	23,641	21,538
Other adjustments	(564)	(145)	164	(115)
Changes in certain assets and liabilities:
Accounts receivable	70,624	(163,465)	9,562	(282,283)
Inventories	64,941	(90,312)	104,410	(171,023)
Other assets	7,292	(630)	7,593	(735)
Accounts payable	(58,484)	48,919	(55,278)	115,251
Income taxes receivable/payable	(36,428)	22,579	13,422	86,541
Accrued expenses	15,805	47,361	(147,534)	(29,390)
Net cash provided by operating activities	361,473	326,033	543,026	503,968
Investing activities:
Purchases of property, plant and equipment	(85,120)	(55,203)	(139,556)	(105,809)
Purchases of short-term investments	(49,465)	(50,000)	(99,142)	(90,000)
Proceeds from maturities of short-term investments	109,034		213,771
Acquisition of business, net of cash and restricted cash acquired		(396,409)	(93,412)	(396,409)
Other investing activities	913	657	1,277	886
Net cash used in investing activities	(24,638)	(500,955)	(117,062)	(591,332)
Financing activities:
Issuance of current and long-term debt	125,222	124,571	246,456	217,629
Repayment of current and long-term debt	(133,875)	(118,089)	(249,146)	(231,123)
Dividends paid	(53,503)	(44,268)	(95,742)	(81,065)
Purchases of treasury stock	(93,136)	(49,145)	(177,444)	(118,414)
Other financing activities	(12)	(3,144)	(5,732)	(8,324)
Net cash used in financing activities	(155,304)	(90,075)	(281,608)	(221,297)
Increase (decrease) in cash, cash equivalents, and restricted cash	181,531	(264,997)	144,356	(308,661)
Cash, cash equivalents, and restricted cash at beginning of period	797,248	991,421	834,423	1,035,085
Cash, cash equivalents, and restricted cash at end of period	978,779	726,424	978,779	726,424
Supplemental disclosure information:
Cash paid for interest	53,981	53,226	62,587	61,855
Cash paid for income taxes, net	$ 84,516	$ 79,995	$ 86,355	$ 78,950