Long-Term Debt (Detail) - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
$2,000 Credit Facility	$ 0	$ 0
Other	116,000,000	123,000,000
Long-term debt	4,304,000,000	3,781,000,000
Current portion of long-term debt	(615,000,000)	(324,000,000)
Long-term debt, noncurrent	3,689,000,000	3,457,000,000
Multicurrency revolving credit agreement, aggregate borrowings	2,000,000,000	2,000,000,000
Series G, Senior Notes 5.8% Due November 10, 2015
Debt Instrument [Line Items]
Senior Notes	316,000,000	314,000,000
Series H, Senior Notes 6.2% Due June 15, 2016
Debt Instrument [Line Items]
Senior Notes	289,000,000	289,000,000
Series I, Senior Notes 6.4% Due June 15, 2017
Debt Instrument [Line Items]
Senior Notes	293,000,000	293,000,000
Series K, Senior Notes 3.0% Due March 1, 2019
Debt Instrument [Line Items]
Senior Notes	597,000,000	596,000,000
Series L, Senior Notes 3.3% Due September 15, 2022
Debt Instrument [Line Items]
Senior Notes	349,000,000	349,000,000
Series M, Senior Notes 3.4% Due October 15, 2020
Debt Instrument [Line Items]
Senior Notes	348,000,000	348,000,000
Series N, Senior Notes 3.1% Due October 15, 2021
Debt Instrument [Line Items]
Senior Notes	398,000,000	397,000,000
Series O, Senior Notes 2.9% Due March 1, 2021
Debt Instrument [Line Items]
Senior Notes	449,000,000	0
Series P, Senior Notes 3.8% Due October 1, 2025
Debt Instrument [Line Items]
Senior Notes	$ 346,000,000	$ 0
Senior Notes \| Series G, Senior Notes 5.8% Due November 10, 2015
Debt Instrument [Line Items]
Debt instrument, stated interest rate	5.80%	5.80%
Senior Notes, face amount	$ 316,000,000	$ 316,000,000
Senior Notes, effective interest rate	6.80%	6.80%
Senior Notes \| Series H, Senior Notes 6.2% Due June 15, 2016
Debt Instrument [Line Items]
Debt instrument, stated interest rate	6.20%	6.20%
Senior Notes, face amount	$ 289,000,000	$ 289,000,000
Senior Notes, effective interest rate	6.30%	6.30%
Senior Notes \| Series I, Senior Notes 6.4% Due June 15, 2017
Debt Instrument [Line Items]
Debt instrument, stated interest rate	6.40%	6.40%
Senior Notes, face amount	$ 293,000,000	$ 293,000,000
Senior Notes, effective interest rate	6.50%	6.50%
Senior Notes \| Series K, Senior Notes 3.0% Due March 1, 2019
Debt Instrument [Line Items]
Debt instrument, stated interest rate	3.00%	3.00%
Senior Notes, face amount	$ 600,000,000	$ 600,000,000
Senior Notes, effective interest rate	4.40%	4.40%
Senior Notes \| Series L, Senior Notes 3.3% Due September 15, 2022
Debt Instrument [Line Items]
Debt instrument, stated interest rate	3.30%	3.30%
Senior Notes, face amount	$ 350,000,000	$ 350,000,000
Senior Notes, effective interest rate	3.40%	3.40%
Senior Notes \| Series M, Senior Notes 3.4% Due October 15, 2020
Debt Instrument [Line Items]
Debt instrument, stated interest rate	3.40%	3.40%
Senior Notes, face amount	$ 350,000,000	$ 350,000,000
Senior Notes, effective interest rate	3.60%	3.60%
Senior Notes \| Series N, Senior Notes 3.1% Due October 15, 2021
Debt Instrument [Line Items]
Debt instrument, stated interest rate	3.10%	3.10%
Senior Notes, face amount	$ 400,000,000	$ 400,000,000
Senior Notes, effective interest rate	3.40%	3.40%
Senior Notes \| Series O, Senior Notes 2.9% Due March 1, 2021
Debt Instrument [Line Items]
Debt instrument, stated interest rate	2.875%	2.875%
Senior Notes, face amount	$ 450,000,000	$ 450,000,000
Senior Notes, effective interest rate	3.10%	3.10%
Senior Notes \| Series P, Senior Notes 3.8% Due October 1, 2025
Debt Instrument [Line Items]
Debt instrument, stated interest rate	3.75%	3.75%
Senior Notes, face amount	$ 350,000,000	$ 350,000,000
Senior Notes, effective interest rate	4.00%	4.00%
Commercial Paper
Debt Instrument [Line Items]
Commercial paper, average interest rate of 0.5% at September 30, 2015	$ 803,000,000	$ 1,072,000,000
Long-term debt, average interest rate	0.50%

Long-term Debt and Capital Lease Obligations, Other

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Carrying value as of the balance sheet date of long-term unsecured obligations issued by corporations and other borrowers to investors (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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-Publisher FASB

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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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.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Weighted average interest rate of long-term debt outstanding.

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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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