CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Proceeds from (Payments to) Noncontrolling Interests	$ 156	$ 165	$ 0
Cash flow from operating activities:
Net income (loss)	865	(189)	2,894
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, depletion and amortization	1,528	1,412	1,754
Tax Cuts and Jobs Act of 2017, provisional income tax expense (benefit)	0	0	(123)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	0
Payments for Legal Settlements	(139)	(187)	(56)
Net gain on sales of assets	(473)	(417)	(208)
Stock-based compensation	99	63	76
Net charges for environmental and asset retirement obligations, including accretion	181	221	262
Payments for environmental and asset retirement obligations	216	244	239
Pension and Other Postretirement Benefits Expense (Reversal of Expense), Noncash	65	108	81
Payment for Pension and Other Postretirement Benefits	(121)	(75)	(75)
Net loss (gain) on early extinguishment of debt	101	27	(7)
Deferred income taxes	181	29	100
Proceeds from Dividends Received		40	0
PT-FI Surface Water Tax, Withholding Tax and Environmental Matters, Expense	(19)	30	162
PT-FI Surface Water Tax, Withholding Tax and Environmental Matters, Payments	(14)	(67)	0
Cerro Verde royalty dispute, charges	32	65	371
Other Operating Activities, Cash Flow Statement	53	138	27
Changes in working capital and other:
Accounts receivable	132	119	649
Inventories	42	259	(537)
Other current assets	(27)	60	(28)
Accounts payable and accrued liabilities	115	(60)	(106)
Accrued income taxes and timing of other tax payments	403	(29)	(634)
Net cash provided by operating activities	3,017	1,482	3,863
Cash flow from investing activities:
Capital expenditures	(1,961)	(2,652)	(1,971)
Acquisition of PT Rio Tinto Indonesia	0	0	(3,500)
Proceeds from sales of:
Proceeds from sales	0
Other, net	(7)	(12)	(97)
Net cash used in investing activities	(1,264)	(2,103)	(5,018)
Cash flow from financing activities:
Proceeds from debt	3,531	1,879	632
Repayments of debt	(3,724)	(3,197)	(2,717)
Proceeds from sale of PT-FI shares	0	0	3,500
Cash dividends and distributions paid:
Common stock	(73)	(291)	(218)
Noncontrolling interests	0	(82)	(278)
Other, net	(18)	(30)	(19)
Net cash (used in) provided by financing activities	(128)	(1,556)	900
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	1,625	(2,177)	(255)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	3,903	2,278	4,455
Inventory Adjustment	96	179	4
PT Indonesia Papua Metal dan Mineral
Proceeds from sales of:
Proceeds from sales		0	457
Timok and a portion of Freeport Cobalt [Member]
Proceeds from sales of:
Proceeds from sales	0	452	0
Kisanfu Exploration Project
Proceeds from sales of:
Proceeds from sales	550	0	0
Other Assets
Proceeds from sales of:
Proceeds from sales	154	109	93
North America copper mines
Cash flow from investing activities:
Capital expenditures	(428)	(877)	(601)
South America
Cash flow from investing activities:
Capital expenditures	(183)	(256)	(237)
Indonesia
Cash flow from investing activities:
Capital expenditures	(1,266)	(1,369)	(1,001)
Molybdenum mines
Cash flow from investing activities:
Capital expenditures	(19)	(19)	(9)
Other
Cash flow from investing activities:
Capital expenditures	(65)	(131)	(123)
PT-FI
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	0	(504)
Asbestos Contamination in Talc-Based Personal Care Products [Member]
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Settlement expense	(130)	$ 0	$ 0
PT Smelting
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Proceeds from Dividends Received	$ 3