Debt (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Senior notes	$ 3,065	$ 2,776
Credit facility, including term loans of $997	2,471	989
Other debt	5	29
Total debt	5,541	3,794
Series C senior notes 4.75% due March 2023
Debt Instrument [Line Items]
Senior notes		447
Series D senior notes 3.75% due October 2023
Debt Instrument [Line Items]
Senior notes	399	398
Series E senior notes 4% due June 2025
Debt Instrument [Line Items]
Senior notes	497	497
Series G senior notes 3.875% due April 2024
Debt Instrument [Line Items]
Senior notes	398	397
Series I senior notes 3.5% due September 2030
Debt Instrument [Line Items]
Senior notes	734
Series F senior notes 4.5% due February 2026
Debt Instrument [Line Items]
Senior notes	397	397
Series H senior notes 3.375% due December 2029
Debt Instrument [Line Items]
Senior notes	640	640
Term Loan due January 2024
Debt Instrument [Line Items]
Credit facility, including term loans of $997	498	498
Term Loan due January 2025
Debt Instrument [Line Items]
Credit facility, including term loans of $997	499	499
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility	$ 1,474	$ (8)

Line of credit including deferred financing costs.

No definition available.

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- Definition

Amount of short-term and long-term debt and lease obligation.

+ References

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-Publisher FASB
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- Definition

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.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

+ References

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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-Publisher FASB
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