Retirement Plans - Components of Net Periodic Benefit Cost for Pension Plans & Postretirement Medical Plan (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Settlement loss	$ 17	$ 2	$ 9
Net non-service pension (income) costs included in Other, net	(39)	(114)	(75)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	35	44	51
Interest cost	97	69	55
Expected return on plan assets	(156)	(196)	(197)
Amortization of unrecognized net actuarial losses (gains)	3	11	58
Settlement loss	17	2	9
Net Periodic Benefit Cost	(4)	(70)	(24)
Postretirement Medical Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	3	3	3
Interest cost	2	1	1
Expected return on plan assets	0	0	0
Amortization of unrecognized net actuarial losses (gains)	(2)	(1)	(1)
Settlement loss	0	0	0
Net Periodic Benefit Cost	$ 3	$ 3	$ 3