POSTRETIREMENT BENEFIT PLANS - Effect on Operations of Pension Plans (Details) - Principal pension plans - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Service cost for benefits earned	$ 21	$ 49
Expected return on plan assets	(594)	(786)
Interest cost on benefit obligations	474	517
Net actuarial loss amortization	(172)	363
Benefit plans cost	(271)	143
Discontinued operations
Defined Benefit Plan Disclosure [Line Items]
Benefit plans cost	0	49
Continuing operations
Defined Benefit Plan Disclosure [Line Items]
Benefit plans cost	$ (271)	$ 94