Long-Term Debt (Detail) - USD ($)	Jun. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Credit Facility	$ 0	$ 0
Other	108,000,000	113,000,000
Total debt	4,360,000,000	4,107,000,000
Less: Current portion of long-term debt	(303,000,000)	(300,000,000)
Long-term debt, noncurrent	4,057,000,000	3,807,000,000
Series H Notes, interest rate of 6.2%, face amount of $289, matured June 15, 2016 (effective interest rate of 6.3%)
Debt Instrument [Line Items]
Senior notes	0	289,000,000
Series I Notes, interest rate of 6.4%, face amount of $293, maturing June 15, 2017 (effective interest rate of 6.5%)
Debt Instrument [Line Items]
Senior notes	293,000,000	293,000,000
Series K Notes, interest rate of 3.0%, face amount of $600, maturing March 1, 2019 (effective interest rate of 4.4%)
Debt Instrument [Line Items]
Senior notes	596,000,000	595,000,000
Series L Notes, interest rate of 3.3%, face amount of $350, maturing September 15, 2022 (effective interest rate of 3.4%)
Debt Instrument [Line Items]
Senior notes	348,000,000	348,000,000
Series M Notes, interest rate of 3.4%, face amount of $350, maturing October 15, 2020 (effective interest rate of 3.6%)
Debt Instrument [Line Items]
Senior notes	347,000,000	347,000,000
Series N Notes, interest rate of 3.1%, face amount of $400, maturing October 15, 2021 (effective interest rate of 3.4%)
Debt Instrument [Line Items]
Senior notes	395,000,000	395,000,000
Series O Notes, interest rate of 2.9%, face amount of $450, maturing March 1, 2021 (effective interest rate of 3.1%)
Debt Instrument [Line Items]
Senior notes	446,000,000	446,000,000
Series P Notes, interest rate of 3.8%, face amount of $350, maturing October 1, 2025 (effective interest rate of 4.0%)
Debt Instrument [Line Items]
Senior notes	344,000,000	343,000,000
Series Q Notes, interest rate of 2.3%, face amount of $750, maturing January 15, 2022 (effective interest rate of 2.5%)
Debt Instrument [Line Items]
Senior notes	741,000,000	0
Series R Notes, interest rate of 3.1%, face amount of $750, maturing June 15, 2026 (effective interest rate of 3.3%)
Debt Instrument [Line Items]
Senior notes	$ 742,000,000	$ 0
Senior Notes \| Series H Notes, interest rate of 6.2%, face amount of $289, matured June 15, 2016 (effective interest rate of 6.3%)
Debt Instrument [Line Items]
Senior notes, 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 Notes, interest rate of 6.4%, face amount of $293, maturing June 15, 2017 (effective interest rate of 6.5%)
Debt Instrument [Line Items]
Senior notes, 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 Notes, interest rate of 3.0%, face amount of $600, maturing March 1, 2019 (effective interest rate of 4.4%)
Debt Instrument [Line Items]
Senior notes, 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 Notes, interest rate of 3.3%, face amount of $350, maturing September 15, 2022 (effective interest rate of 3.4%)
Debt Instrument [Line Items]
Senior notes, 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 Notes, interest rate of 3.4%, face amount of $350, maturing October 15, 2020 (effective interest rate of 3.6%)
Debt Instrument [Line Items]
Senior notes, 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 Notes, interest rate of 3.1%, face amount of $400, maturing October 15, 2021 (effective interest rate of 3.4%)
Debt Instrument [Line Items]
Senior notes, 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 Notes, interest rate of 2.9%, face amount of $450, maturing March 1, 2021 (effective interest rate of 3.1%)
Debt Instrument [Line Items]
Senior notes, stated interest rate	2.90%	2.90%
Senior notes, face amount	$ 450,000,000	$ 450,000,000
Senior notes, effective interest rate	3.10%	3.10%
Senior Notes \| Series P Notes, interest rate of 3.8%, face amount of $350, maturing October 1, 2025 (effective interest rate of 4.0%)
Debt Instrument [Line Items]
Senior notes, stated interest rate	3.80%	3.80%
Senior notes, face amount	$ 350,000,000	$ 350,000,000
Senior notes, effective interest rate	4.00%	4.00%
Senior Notes \| Series Q Notes, interest rate of 2.3%, face amount of $750, maturing January 15, 2022 (effective interest rate of 2.5%)
Debt Instrument [Line Items]
Senior notes, stated interest rate	2.30%	2.30%
Senior notes, face amount	$ 750,000,000	$ 0
Senior notes, effective interest rate	2.50%	2.50%
Senior Notes \| Series R Notes, interest rate of 3.1%, face amount of $750, maturing June 15, 2026 (effective interest rate of 3.3%)
Debt Instrument [Line Items]
Senior notes, stated interest rate	3.125%	3.10%
Senior notes, face amount	$ 750,000,000	$ 0
Senior notes, effective interest rate	3.30%	3.30%
Commercial Paper
Debt Instrument [Line Items]
Commercial paper	$ 0	$ 938,000,000

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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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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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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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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