INCOME TAXES (Reconciliation of U.S. federal statutory rate to effective tax rate) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Amount
U.S. federal statutory tax rate	$ (1,608)	$ (377)	$ (64)
Valuation allowance	221	(210)	(149)
PT-FI historical tax disputesb	(193)	(8)	(145)
Percentage depletion	221	104	118
Effect of foreign rates different than the U.S. federal statutory rate	(328)	(109)	(64)
Withholding and other impacts on foreign earnings	(678)	(193)	(55)
Adjustment to deferred taxes	0	0	(49)
Non-deductible permanent differences	0	0	(47)
Uncertain tax positions	13	(15)	(47)
U.S. tax reform	0	0	29
Foreign tax credit limitation	(11)	28	(16)
State income taxes	(14)	(2)	16
Cerro Verde historical tax disputese	0	(39)	2
Timok exploration project sale	0	53	(15)
Sale of Kisanfu	0	(135)	0
Other items, net	(111)	(41)	(24)
Provision for income taxes	$ (2,299)	$ (944)	$ (510)
Percent
U.S. federal statutory tax rate	(21.00%)	(21.00%)	(21.00%)
Valuation allowance	3.00%	(12.00%)	(49.00%)
PT-FI historical tax disputesb	(3.00%)	0.00%	(47.00%)
Percentage depletion	3.00%	6.00%	39.00%
Effect of foreign rates different than the U.S. federal statutory rate	(4.00%)	(6.00%)	(21.00%)
Withholding and other impacts on foreign earnings	(9.00%)	(11.00%)	(18.00%)
Adjustment to deferred taxes			(16.00%)
Non-deductible permanent differences			(15.00%)
Uncertain tax positions		(1.00%)	(15.00%)
U.S. tax reform			0.09
Foreign tax credit limitation		2.00%	(5.00%)
State income taxes			6.00%
Cerro Verde historical tax disputese		(2.00%)	1.00%
Timok exploration project sale		3.00%	(5.00%)
Sale of Kisanfu		(8.00%)
Other items, net	(1.00%)	(3.00%)	(9.00%)
Provision for income taxes	(30.00%)	(53.00%)	(166.00%)
Reserve for Taxes, Other than Income Taxes
Schedule Of Income Taxes [Line Items]
Tax Cuts and Jobs Act of 2017, provisional income tax expense (benefit)			$ 29
PT Rio Tinto
Amount
Valuation allowance	$ 189	$ 0	$ 0
Percent
Valuation allowance	2.00%	0.00%	0.00%

Effective Income Tax Rate Reconciliation, Adjustment in Deferred Tax Assets

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