Retirement and Other Benefit Plans - Schedule of Components of Net Periodic Benefit Cost (Detail) - Pension - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 38	$ 33	$ 48
Interest cost	55	51	41
Expected return on assets	(79)	(71)	(77)
Amortization of prior service cost	6	6	4
Amortization of actuarial loss	2	1	4
Settlement charge	0	0	(5)
Net periodic benefit cost	$ 22	$ 20	$ 25