BUSINESS SEGMENTS INFORMATION (Customers and Labor Matters) (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Major Customer and Labor Matters [Line Items]
Segment Reporting, Disclosure of Major Customers			12
Revenues		$ 14,198	$ 14,402	$ 18,628
Affiliated Entity | Noncontrolling Interest Owners Of South America Mining Operations
Major Customer and Labor Matters [Line Items]
Revenues	$ 1,000	900	1,000	1,200
Affiliated Entity | PT Smelting
Major Customer and Labor Matters [Line Items]
Revenues		1,800	1,900	2,200
Indonesia
Major Customer and Labor Matters [Line Items]
Revenues		$ 1,760	$ 1,894	$ 2,226