Debt - Debt (Detail) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Senior Notes	$ 2,482	$ 2,480
Other	232	232
Current and Non-current debt
Total debt	2,714	2,712
Less current portion	8	6
Long-term debt	2,706	2,706
Senior Notes, Interest at 2.60% Payable Semiannually, Principal Due on December 1, 2022 [Member]
Debt Instrument [Line Items]
Senior Notes	1,394	1,392
Senior Notes, Interest at 3.95% Payable Semiannually, Principal Due on December 1, 2042 [Member]
Debt Instrument [Line Items]
Senior Notes	$ 1,088	$ 1,088

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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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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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.

+ References

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- References

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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.

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Amount of long-term debt classified as other.

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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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