Retirement and Other Benefit Plans - Net Periodic Benefit Credit or Cost Not Yet Recognized (Detail) - Pension - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Prior service (credit) - Gross	$ 37	$ 42
Actuarial loss - Gross	17	64
Total - Gross	54	106
Prior service cost (credit) - Net of tax	7	20
Actuarial loss - Net of tax	3	30
Total - Net of tax	$ 10	$ 50

Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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