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Income Taxes - Schedule of Income Taxes (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Tax Disclosure [Abstract]
Income before income taxes	$ 461	$ (105)	$ 773	$ 114
Estimated annualized effective tax rate			28.00%	(183.00%)
Income tax expense (benefit)			$ 217	$ (209)
(Unfavorable) favorable tax impact related to losses in jurisdictions with no tax benefit			(12)	333
Discrete tax (benefit) expense			(1)	1
Provision for income taxes	$ 111	$ 45	$ 204	$ 125

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Unfavorable (favorable) impact income tax expense benefit.

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