Significant Accounting Policies - Reclassifications Out of Accumulated Other Comprehensive Loss (Detail) - Pension and Postretirement Benefit Plans - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Earnings from Continuing Operations	$ 1	$ 1	$ 2	$ 2
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax effect	0	(1)	(1)	(1)
Earnings from Continuing Operations	1	1	2	2
Reclassification out of Accumulated Other Comprehensive Income | Other Nonoperating Income, Net
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of prior service cost	$ 1	$ 2	$ 3	$ 3