Debt - Summary of Debt (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Commercial paper	$ 0	$ 25
Other debt	19	15
Total debt	5,607	5,723
Short-term debt and current portion of long-term debt	(466)	(332)
Long-term debt	5,141	5,391
4.70% senior notes due 2020
Debt Instrument [Line Items]
Senior notes	0	305
3.15% senior notes due 2021
Debt Instrument [Line Items]
Senior notes	94	94
3.75% senior notes due 2021
Debt Instrument [Line Items]
Senior notes	369	342
4.00% senior notes due 2022
Debt Instrument [Line Items]
Senior notes	250	249
3.85% senior notes due 2023
Debt Instrument [Line Items]
Senior notes	1,090	1,388
4.00% senior notes due 2024
Debt Instrument [Line Items]
Senior notes	200	199
4.875% senior notes due 2025
Debt Instrument [Line Items]
Senior notes	492	0
3.90% senior notes due 2025
Debt Instrument [Line Items]
Senior notes	47	47
4.20% senior notes due 2026
Debt Instrument [Line Items]
Senior notes	1,973	1,986
5.375% senior notes due 2036
Debt Instrument [Line Items]
Senior notes	416	416
5.50% senior notes due 2046
Debt Instrument [Line Items]
Senior notes	$ 657	$ 657

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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