ACCUMULATED OTHER COMPREHENSIVE LOSS - Changes in Amounts Included in Our Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	$ 10,767
Translation adjustments	16	$ 9
Total other comprehensive income	29	30
Balance at end of period	10,237	9,328
Pension
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(720)	(1,064)
Other comprehensive income (loss) before reclassifications	(8)	(4)
Amounts reclassified from accumulated other comprehensive loss to earnings	19	24
Total other comprehensive income	11	20
Balance at end of period	(709)	(1,044)
Other Post-Employment Benefits
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(2)	(12)
Other comprehensive income (loss) before reclassifications	1	0
Amounts reclassified from accumulated other comprehensive loss to earnings	1	1
Total other comprehensive income	2	1
Balance at end of period	0	(11)
Translation Adjustments and Other
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	243	254
Translation adjustments	16	9
Total other comprehensive income	16	9
Balance at end of period	259	263
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(479)	(822)
Total other comprehensive income	29	30
Balance at end of period	$ (450)	$ (792)