POSTRETIREMENT BENEFIT PLANS - Effect on Operations of Pension Plans (Details) - Principal pension plans - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Service cost for benefits earned	$ 17	$ 24	$ 37	$ 45
Prior service cost amortization	1	0	4	0
Expected return on plan assets	(390)	(594)	(968)	(1,188)
Interest cost on benefit obligations	315	472	768	946
Net actuarial gain amortization	(103)	(187)	(257)	(359)
Net periodic expense (income)	(160)	(285)	(416)	(556)
Discontinued operations
Defined Benefit Plan Disclosure [Line Items]
Net periodic expense (income)	0	(96)	(88)	(188)
Continuing operations
Defined Benefit Plan Disclosure [Line Items]
Net periodic expense (income)	$ (160)	$ (189)	$ (328)	$ (368)