Indebtedness - Additional Information (Detail) - USD ($)			1 Months Ended
Mar. 31, 2020	Mar. 25, 2020	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Short-term debt	$ 485,000,000		$ 485,000,000
Principal amount	6,759,000,000		6,759,000,000	$ 5,603,000,000
3.75% 2020 Senior Note, due 2025
Debt Instrument [Line Items]
Principal amount	$ 700,000,000	$ 700,000,000	$ 700,000,000
Debt instrument, term		5 years	5 years
Notes payable, interest rate	3.75%	3.75%	3.75%
Commercial Paper
Debt Instrument [Line Items]
Short-term debt	$ 485,000,000		$ 485,000,000
Weighted average maturity at issuance date	77 days
Weighted average remaining maturity period	58 days
Weighted average interest rate	2.38%		2.38%
Principal amount	$ 487,000,000		$ 487,000,000

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Face (par) amount of debt instrument at time of issuance.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average interest rate of debt outstanding.

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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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