CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Cash Flows [Abstract]
Cash and cash equivalents at beginning of year	$ 746,724	$ 613,110	$ 555,320
Cash flows from operating activities:
Net income	199,942	446,615	604,357
Adjustments to reconcile net income to cash flows from operating activities:
Depreciation and amortization	254,000	231,984	213,484
Gain on sale of business/interest in properties, net	(295,971)	(7,168)	0
Gain on sale of property	0	0	(14,411)
Stock-based compensation and other	20,120	22,837	19,680
Equity in net income of unconsolidated investments (net of tax)	(95,770)	(127,521)	(129,568)
Dividends received from unconsolidated investments and nonmarketable securities	78,391	88,161	71,746
Pension and postretirement (benefit) expense	(74,010)	45,658	31,515
Pension and postretirement contributions	(30,253)	(16,434)	(16,478)
Unrealized gain on investments in marketable securities	(3,818)	(4,635)	(2,809)
Loss on early extinguishment of debt	28,955	0	4,829
Deferred income taxes	(38,500)	(1,976)	14,394
Changes in current assets and liabilities, net of effects of acquisitions and divestitures:
(Increase) decrease in accounts receivable	(49,295)	100,118	(18,220)
(Increase) decrease in inventories	(127,401)	51,978	(46,304)
Decrease (increase) in other current assets	17,411	7,902	(32,941)
Increase (decrease) in accounts payable	143,939	(31,519)	(12,234)
Increase (decrease) in accrued expenses and income taxes payable	127,068	(215,011)	(4,640)
Non-cash transfer of 40% value of construction in progress of Kemerton plant to MRL	135,928	179,437	164,496
Other, net	53,521	28,488	(127,522)
Net cash provided by operating activities	344,257	798,914	719,374
Cash flows from investing activities:
Acquisitions, net of cash acquired	0	(22,572)	(820,000)
Capital expenditures	(953,667)	(850,477)	(851,796)
Cash proceeds from divestitures, net	289,791	0	0
Proceeds from sale of joint venture	0	11,000	0
Proceeds from sale of property and equipment	0	0	10,356
Sales of marketable securities, net	3,774	903	384
Investments in equity and other corporate investments	(6,488)	(2,427)	(2,569)
Net cash used in investing activities	(666,590)	(863,573)	(1,663,625)
Cash flows from financing activities:
Proceeds from issuance of common stock	1,453,888	0	0
Proceeds from borrowings of other long-term debt	0	452,163	1,597,807
Repayments of long-term debt and credit agreements	(1,173,823)	(250,000)	(175,215)
Other borrowings (repayments), net	60,991	137,635	(126,364)
Fees related to early extinguishment of debt	(24,877)	0	(4,419)
Dividends paid to shareholders	(177,853)	(161,818)	(152,204)
Dividends paid to noncontrolling interests	(96,136)	(32,061)	(83,187)
Proceeds from exercise of stock options	18,392	40,437	4,814
Withholding taxes paid on stock-based compensation award distributions	(8,140)	(5,143)	(11,031)
Other	(2,230)	(3,952)	(7,514)
Net cash provided by financing activities	50,212	177,261	1,042,687
Net effect of foreign exchange on cash and cash equivalents	(35,331)	21,012	(40,646)
(Decrease) increase in cash and cash equivalents	(307,452)	133,614	57,790
Cash and cash equivalents at end of year	$ 439,272	$ 746,724	$ 613,110