PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Schedule of Other Changes in Plan Assets and Benefit Obligations Recognized in OCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plan [Line Items]
Current year actuarial loss / (gain)	$ (56)	$ 78	$ 6
Current year prior service cost (credit)	0	(156)	(9)
Total recognized in other comprehensive income (loss) (pre-tax)	$ (104)	$ (171)	$ (52)
Amortization of actuarial losses (in years)	21 years
Amortization of prior service credit (in years)	13 years
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plan [Line Items]
Current year actuarial loss / (gain)	$ (9)
Actuarial (loss) recognized during the year	0
Current year prior service cost (credit)	0
Prior service credit (cost) recognized during the year	47
Total recognized in other comprehensive income (loss) (pre-tax)	38
Total recognized in net periodic benefit costs and other comprehensive income (loss) (pre-tax)	(3)
United States Pension Benefits | Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plan [Line Items]
Current year actuarial loss / (gain)	27
Actuarial (loss) recognized during the year	(74)
Current year prior service cost (credit)	0
Prior service credit (cost) recognized during the year	0
Total recognized in other comprehensive income (loss) (pre-tax)	(47)
Total recognized in net periodic benefit costs and other comprehensive income (loss) (pre-tax)	(51)
Foreign Pension Benefits | Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plan [Line Items]
Current year actuarial loss / (gain)	(74)
Actuarial (loss) recognized during the year	(21)
Current year prior service cost (credit)	0
Prior service credit (cost) recognized during the year	0
Total recognized in other comprehensive income (loss) (pre-tax)	(95)
Total recognized in net periodic benefit costs and other comprehensive income (loss) (pre-tax)	$ (89)