INCOME TAXES (Components of deferred tax assets and liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Foreign tax credits	$ 1,641	$ 1,716
Accrued expenses	1,194	1,108
Net operating losses	2,443	2,249
Employee benefit plans	171	198
Other	238	267
Deferred tax assets	5,687	5,538
Valuation allowances	(4,732)	(4,576)
Net deferred tax assets	955	962
Deferred tax liabilities:
Property, plant, equipment and mine development costs	(4,500)	(4,372)
Undistributed earnings	(694)	(639)
Other	(169)	(157)
Total deferred tax liabilities	(5,363)	(5,168)
Net deferred tax liabilities	$ (4,408)	$ (4,206)