Financial Instruments, Hedging Activities and Fair Value Measurements (Fair Value Additional Information) (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Long-term debt	$ 5,296	$ 5,031
Long-term debt (excluding capital lease obligations), fair values	5,875	5,363
Finance lease liability	12
Capital lease obligations		11
Short-term borrowings	$ 403	$ 10

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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