Retirement and Other Benefit Plans - Net Periodic Benefit Cost Recognized Pretax Amounts in Comprehensive Earnings (Detail) - Pension - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Actuarial (gain) loss	$ (44)	$ 21	$ (115)
Prior service cost	0	0	48
Prior service cost	(6)	(6)	(4)
Actuarial loss	(2)	(1)	(4)
Settlement charge	0	0	(5)
Total	$ (52)	$ 14	$ (80)

Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan.

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Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

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Amount, before tax, after reclassification adjustment, of increase (decrease) in accumulated other comprehensive income from gain (loss) of defined benefit plan.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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