Business Developments and Risks and Uncertainties (Schedule of Results of Operations from Discontinued Operation) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Revenues
Revenues	$ 3	$ 24
Cost of sales	1	11
Total revenues from discontinued operations	2	13
Expenses:
Operating	1	13
Interest	0	1
Increase (decrease) on loss on disposal group	1	(2)
Total expenses from discontinued operations	2	12
Income (loss) before income taxes from discontinued operations	0	1
Provision (benefit) for income taxes from discontinued operations	0	0
Income (loss) from discontinued operations, net of income taxes	$ 0	$ 1

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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Disposal group including discontinued operations total expenses from discontinued operations.

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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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Amount of costs of goods sold attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of gross profit attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of interest expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. 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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