Business Developments and Risks and Uncertainties (Schedule of Results of Operations from Discontinued Operation) (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Revenues
Revenues	$ 3	$ 11	$ 9	$ 57
Cost of sales	2	5	4	27
Total revenues from discontinued operations	1	6	5	30
Expenses:
Operating	1	6	4	30
Interest	0	1	0	3
Increase (decrease) on loss on disposal group	1	0	2	(1)
Total expenses from discontinued operations	2	7	6	32
Income (loss) before income taxes from discontinued operations	(1)	(1)	(1)	(2)
Provision (benefit) for income taxes from discontinued operations	0	0	0	0
Income (loss) from discontinued operations, net of income taxes	$ (1)	$ (1)	$ (1)	$ (2)

Discontinued operation income loss on disposal group held for sale discontinued operation.

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Disposal group including discontinued operation expenses.

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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