CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities:
Net income	$ 438,755	$ 190,836
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	86,919	80,259
Equity-based compensation	17,040	17,844
Deferred income taxes	66,744	5,927
Other adjustments	(662)	(264)
Changes in certain assets and liabilities:
Accounts receivable	(394,545)	(154,072)
Inventories	(374,588)	44,505
Other assets	5,828	(1,541)
Accounts payable	360,681	51,596
Income taxes receivable/payable	59,593	52,385
Accrued expenses	(3,574)	(76,194)
Net cash provided by operating activities	262,191	211,281
Investing activities:
Purchases of property, plant and equipment	(309,863)	(217,535)
Purchases of short-term investments		(149,359)
Proceeds from maturities of short-term investments		192,340
Other investing activities	390	518
Net cash used in investing activities	(309,473)	(174,036)
Financing activities:
Issuance of current and long-term debt	297,441	216,261
Repayment of current and long-term debt	(304,284)	(235,757)
Dividends paid	(52,729)	(51,481)
Purchases of treasury stock		(106,529)
Other financing activities	(16,598)	(6,152)
Net cash used in financing activities	(76,170)	(183,658)
Decrease in cash, cash equivalents, and restricted cash	(123,452)	(146,413)
Cash, cash equivalents, and restricted cash at beginning of period	1,374,122	1,387,397
Cash, cash equivalents, and restricted cash at end of period	1,250,670	1,240,984
Supplemental disclosure information:
Cash paid for interest	11,315	8,785
Cash paid for income taxes, net	$ 2,142	$ 518