Business Developments and Risks and Uncertainties (Schedule of Discontinued Operations Components of Assets and Liabilities Held for Sale) (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Assets held for sale
Cash	$ 10	$ 12
Accounts receivable	21	24
Goodwill	90	90
Other assets	13	8
Loss on disposal group	(51)	(54)
Total assets held for sale	83	80
Liabilities held for sale
Accounts payable	11	12
Debt	34	30
Accrued expenses and other	23	19
Total liabilities held for sale	$ 68	$ 61

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