LONG-TERM DEBT - Detail on Long-term Debt Balances (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Credit Facility	$ 0	$ 0
Capital lease obligations	171	173
Long-term debt	8,238	8,506
Less: Current portion of long-term debt	(398)	(309)
Long-term debt, noncurrent	7,840	8,197
Commercial paper
Debt Instrument [Line Items]
Commercial paper	2,371	2,311
Other
Debt Instrument [Line Items]
Other	279	291
Series I Notes, interest rate of 6.4%, face amount of $293, matured June 15, 2017 (effective interest rate of 6.5%)
Debt Instrument [Line Items]
Senior Notes	$ 0	293
Series I Notes, interest rate of 6.4%, face amount of $293, matured June 15, 2017 (effective interest rate of 6.5%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	6.40%
Senior notes, face amount	$ 293
Senior notes, effective interest rate	6.50%
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	$ 598	597
Series K Notes, interest rate of 3.0%, face amount of $600, maturing March 1, 2019 (effective interest rate of 4.4%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	3.00%
Senior notes, face amount	$ 600
Senior notes, effective interest rate	4.40%
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	348
Series L Notes, interest rate of 3.3%, face amount of $350, maturing September 15, 2022 (effective interest rate of 3.4%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	3.30%
Senior notes, face amount	$ 350
Senior notes, effective interest rate	3.40%
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	$ 348	347
Series M Notes, interest rate of 3.4%, face amount of $350, maturing October 15, 2020 (effective interest rate of 3.6%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	3.40%
Senior notes, face amount	$ 350
Senior notes, effective interest rate	3.60%
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	$ 397	396
Series N Notes, interest rate of 3.1%, face amount of $400, maturing October 15, 2021 (effective interest rate of 3.4%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	3.10%
Senior notes, face amount	$ 400
Senior notes, effective interest rate	3.40%
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	$ 447	446
Series O Notes, interest rate of 2.9%, face amount of $450, maturing March 1, 2021 (effective interest rate of 3.1%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	2.90%
Senior notes, face amount	$ 450
Senior notes, effective interest rate	3.10%
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	$ 345	344
Series P Notes, interest rate of 3.8%, face amount of $350, maturing October 1, 2025 (effective interest rate of 4.0%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	3.80%
Senior notes, face amount	$ 350
Senior notes, effective interest rate	4.00%
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	$ 744	742
Series Q Notes, interest rate of 2.3%, face amount of $750, maturing January 15, 2022 (effective interest rate of 2.5%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	2.30%
Senior notes, face amount	$ 750
Senior notes, effective interest rate	2.50%
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	$ 743	742
Series R Notes, interest rate of 3.1%, face amount of $750, maturing June 15, 2026 (effective interest rate of 3.3%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	3.10%
Senior notes, face amount	$ 750
Senior notes, effective interest rate	3.30%
Series S Notes, interest rate of 6.8%, face amount of $324, maturing May 15, 2018 (effective interest rate of 1.7%)
Debt Instrument [Line Items]
Senior Notes	$ 330	346
Series S Notes, interest rate of 6.8%, face amount of $324, maturing May 15, 2018 (effective interest rate of 1.7%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	6.80%
Senior notes, face amount	$ 324
Senior notes, effective interest rate	1.70%
Series T Notes, interest rate of 7.2%, face amount of $181, maturing December 1, 2019 (effective interest rate of 2.3%)
Debt Instrument [Line Items]
Senior Notes	$ 197	206
Series T Notes, interest rate of 7.2%, face amount of $181, maturing December 1, 2019 (effective interest rate of 2.3%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	7.20%
Senior notes, face amount	$ 181
Senior notes, effective interest rate	2.30%
Series U Notes, interest rate of 3.1%, face amount of $291, maturing February 15, 2023 (effective interest rate of 3.1%)
Debt Instrument [Line Items]
Senior Notes	$ 291	291
Series U Notes, interest rate of 3.1%, face amount of $291, maturing February 15, 2023 (effective interest rate of 3.1%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	3.10%
Senior notes, face amount	$ 291
Senior notes, effective interest rate	3.10%
Series V Notes, interest rate of 3.8%, face amount of $318, maturing March 15, 2025 (effective interest rate of 2.8%)
Debt Instrument [Line Items]
Senior Notes	$ 337	340
Series V Notes, interest rate of 3.8%, face amount of $318, maturing March 15, 2025 (effective interest rate of 2.8%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	3.80%
Senior notes, face amount	$ 318
Senior notes, effective interest rate	2.80%
Series W Notes, interest rate of 4.5%, face amount of $278, maturing October 1, 2034 (effective interest rate of 4.1%)
Debt Instrument [Line Items]
Senior Notes	$ 292	$ 293
Series W Notes, interest rate of 4.5%, face amount of $278, maturing October 1, 2034 (effective interest rate of 4.1%) \| Senior Notes
Debt Instrument [Line Items]
Senior notes, interest rate	4.50%
Senior notes, face amount	$ 278
Senior notes, effective interest rate	4.10%

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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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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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, 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.

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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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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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