Income Taxes (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Income Taxes [Line Items]
Income tax expense	$ (5)	$ (1)	$ (6)	$ (2)
U.S. Federal Tax
Income Taxes [Line Items]
Income tax expense			$ 0	$ 0

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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+ Details