Debt - Debt (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Senior Notes	$ 1,764	$ 1,980
Other debt	70	9
Long-term debt	1,834	1,989
Senior Notes, Interest at 3.95% Payable Semiannually, Principal Due on December 1, 2042 [Member]
Debt Instrument [Line Items]
Senior Notes	1,089	1,088
Senior Notes, Interest at 3.60% Payable Semiannually, Principal Due on December 1, 2029 [Member]
Debt Instrument [Line Items]
Senior Notes	493	493
Senior Notes, Interest at 2.60% Payable Semiannually, Principal Due on December 1, 2022 [Member]
Debt Instrument [Line Items]
Senior Notes	$ 182	$ 399

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.

No definition available.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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Amount of long-term debt classified as other.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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