Pension and Other Postretirement Benefits - Components of Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		$ 1	$ 3	$ 3	$ 5
Interest cost	[1]	25	27	50	54
Expected return on plan assets	[1]	(31)	(35)	(62)	(70)
Recognized net actuarial loss	[1]	9	8	18	16
Curtailments	[2]				1
Settlements	[2]		(1)		(1)
Net periodic benefit cost		4	2	9	5
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		1		1	1
Interest cost	[1]	6	6	11	12
Recognized net actuarial loss	[1]	1	2	2	3
Amortization of prior service benefit	[1]	(3)	(4)	(6)	(7)
Net periodic benefit cost		$ 5	$ 4	$ 8	$ 9

[1] These amounts were reported in Other (income) expenses, net on the accompanying Statement of Consolidated Operations (see Note P).

[2] These amounts were reported in Restructuring and other charges, net on the accompanying Statement of Consolidated Operations and Cash Flows.