Business Developments and Risks and Uncertainties (Schedule of Results of Operations from Discontinued Operation) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Revenues
Revenues	$ 32
Cost of sales	17
Total revenues from discontinued operations	15
Expenses
Operating	20
Interest	1
Increase (decrease) on loss on disposal group	(3)
Total expenses from discontinued operations	18
Income (loss) before income taxes from discontinued operations	(3)
Provision (benefit) for income taxes from discontinued operations	0
Income (loss) from discontinued operations, net of income taxes	$ (3)	$ 0

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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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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