Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities:
Net earnings	$ 836,028	$ 1,370,910	$ 2,481,084
Adjustments:
Depreciation	702,110	648,911	630,879
Amortization	83,356	85,742	88,758
Stock-based compensation	73,853	90,359	73,422
Deferred income taxes	162,836	99,157	3,017
Distributions from affiliates	10,521	37,459	30,196
Equity in losses (earnings) of unconsolidated subsidiaries	10,533	(3,311)	(40,240)
Losses and impairments of assets	613,640	66,916	110,000
Changes in assets and liabilities (exclusive of acquisitions and dispositions):
Accounts receivable	(129,290)	361,340	(485,433)
Inventories	284,081	712,645	(1,092,101)
Accounts payable	250,561	(253,457)	235,572
Federal income taxes	(197,275)	(180,325)	163,743
Salaries, wages and related accruals	(41,169)	(186,755)	204,796
Other operating activities	37,092	(40,178)	(9,741)
Cash provided by operating activities	2,696,877	2,809,413	2,393,952
Investing activities:
Capital expenditures	(1,543,219)	(1,477,293)	(982,531)
Investment in and advances to affiliates	(44,427)	(45,834)	(121,412)
Divestiture of affiliates		67,591
Disposition of plant and equipment	40,933	41,618	31,589
Acquisitions (net of cash acquired)	(88,071)	(83,106)	(33,063)
Purchases of investments	(488,517)	(367,741)
Proceeds from the sale of investments	392,178	67,701	50,000
Other investing activities	(33,171)	2,873	25,348
Cash used in investing activities	(1,764,294)	(1,794,191)	(1,030,069)
Financing activities:
Net change in short-term debt	(4,538)	4,574	5,037
Proceeds from long-term debt, net of discount	1,237,635		995,710
Repayment of long-term debt	(97,150)		(500,000)
Premium on debt exchange	(180,383)
Bond issuance related costs	(6,250)		(7,625)
Issuance of common stock	11,846	16,145	24,101
Payment of tax withholdings on certain stock-based compensation	(19,102)	(25,047)	(22,123)
Distributions to noncontrolling interests	(115,508)	(76,347)	(56,179)
Cash dividends	(491,655)	(492,062)	(485,376)
Acquisition of treasury stock	(39,499)	(298,541)	(853,997)
Other financing activities	(9,542)	(9,132)	(7,725)
Cash provided by (used in) financing activities	285,854	(880,410)	(908,177)
Effect of exchange rate changes on cash	1,887	907	(5,924)
Increase in cash and cash equivalents and restricted cash and cash equivalents	1,220,324	135,719	449,782
Cash and cash equivalents - beginning of year	1,534,605	1,398,886	949,104
Cash and cash equivalents and restricted cash and cash equivalents - end of year	2,754,929	1,534,605	1,398,886
Non-cash investing activity:
Change in accrued plant and equipment purchases	$ (16,103)	$ 34,777	$ 14,725