Pension Plans and Other Postretirement Benefits - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Gain due to settlement	$ 12,000,000	$ 0	$ 0
Assumptions used calculating net periodic benefit sensitivity rate increase decrease discount rate	0.25%
Effect of 25 basis point increase in rate of return on pension expense	$ 8,000,000
Effect of 25 basis point decrease in rate of return on pension expense	1,000,000
Effect of 25 basis point decrease in discount rate on benefit obligation	48,000,000
Effect of 25 basis point increase in discount rate on benefit obligation	$ 50,000,000
Annual rate of increase in health care cost assumed for next fiscal year	7.00%
Defined Benefit Plan, ultimate health care cost trend rate	5.00%
Period for decreasing the annual rate	eight years
Defined benefit pension plans	$ 828,000,000
Percentage of total assets	26.00%
Qualified benefit pension plans	$ 0
Percentage of pension plan assets that is not exceeded by investment in security of single Non-US Government of Government agency	10.00%
Defined contribution pension and retirement savings plans total expense	$ 62,000,000	56,000,000	45,000,000
Percentage of eligible employees contribution for retirement savings plan	50.00%
Percentage of employer matching contribution to employee's contribution	100.00%
Maximum employer contribution on Employee's qualified contribution	5.00%
Qualified defined contribution plans expense during the period	$ 100,000,000	96,000,000	84,000,000
Other Investments | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets	5.00%
Other Investments | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets	60.00%
Total Debt Securities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets	10.00%
Total Debt Securities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets	65.00%
Equity Securities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets	25.00%
Equity Securities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets	60.00%
Supplemental Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 132,000,000	146,000,000
Accumulated benefit obligation	132,000,000	146,000,000
Employer contribution	16,000,000	18,000,000
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Gain due to settlement	12,000,000
Decrease for settlement	171,000,000	0
Projected benefit obligation	2,042,000,000	2,369,000,000	2,379,000,000
Accumulated benefit obligation	2,000,000,000.0	2,400,000,000
Employer contribution	16,000,000	18,000,000
Settlements paid	171,000,000	0
Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Decrease for settlement	0	0
Projected benefit obligation	51,000,000	57,000,000	$ 60,000,000
Employer contribution	2,000,000	3,000,000
Settlements paid	$ 0	$ 0