Income Taxes (Income Taxes And Related Effective Tax Rates) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disclosure Income Taxes Income Taxes And Related Effective Tax Rates [Abstract]
Income (loss) from continuing operations before income taxes	$ (185)	$ (35)	$ (346)	$ (144)
Provision (benefit) for income taxes	$ 0	$ 0	$ 0	$ 0
Effective tax rate	0.00%	0.00%	0.00%	0.00%