Retirement and Other Benefit Plans - Schedule of Change In Plan Assets (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Balance at beginning of year	$ 1,177
Employer contributions	34	$ 32
Balance at end of year	1,238	1,177
Pension
Defined Benefit Plan Disclosure [Line Items]
Balance at beginning of year	1,177	1,067
Actual return on plan assets, net	77	123
Employer contributions	34	32
Gross benefits paid	(50)	(45)
Balance at end of year	$ 1,238	$ 1,177