NOTES PAYABLE, LONG-TERM DEBT AND AVAILABLE CREDIT FACILITIES (Schedule of Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Unamortized debt discount and issuance costs	$ (334)	$ (346)
Long-term debt due within one year	(340)	(752)
Long-term debt	19,254	$ 19,765
Maturities of Long-term Debt [Abstract]
2019	340
2020	1,833
2021	6,247
2022	1,510
2023	$ 480
Promissory notes and debentures \| Final maturity 2018
Debt Instrument [Line Items]
Weighted average rate	0.00%	5.78%
Long-term debt, gross	$ 0	$ 339
Promissory notes and debentures \| Final maturity 2019
Debt Instrument [Line Items]
Weighted average rate	9.80%	8.55%
Long-term debt, gross	$ 7	$ 2,122
Promissory notes and debentures \| Final maturity 2020
Debt Instrument [Line Items]
Weighted average rate	4.46%	4.46%
Long-term debt, gross	$ 1,547	$ 1,547
Promissory notes and debentures \| Final maturity 2021
Debt Instrument [Line Items]
Weighted average rate	4.71%	4.71%
Long-term debt, gross	$ 1,424	$ 1,424
Promissory notes and debentures \| Final maturity 2022
Debt Instrument [Line Items]
Weighted average rate	3.50%	3.50%
Long-term debt, gross	$ 1,373	$ 1,373
Promissory notes and debentures \| Final maturity 2023
Debt Instrument [Line Items]
Weighted average rate	7.64%	7.64%
Long-term debt, gross	$ 325	$ 325
Promissory notes and debentures \| Final maturity 2024 and thereafter
Debt Instrument [Line Items]
Weighted average rate	5.73%	5.92%
Long-term debt, gross	$ 8,859	$ 6,857
Promissory notes and debentures \| U.S. dollar loans, various rates and maturities
Debt Instrument [Line Items]
Weighted average rate	3.59%	2.44%
Long-term debt, gross	$ 4,533	$ 4,564
Promissory notes and debentures \| Foreign currency loans, various rates and maturities
Debt Instrument [Line Items]
Weighted average rate	3.21%	3.00%
Long-term debt, gross	$ 713	$ 814
Medium-term notes, varying maturities through 2025
Debt Instrument [Line Items]
Weighted average rate	3.26%	3.20%
Long-term debt, gross	$ 778	$ 873
Tax-exempt bonds, varying maturities through 2038
Debt Instrument [Line Items]
Weighted average rate	0.00%	5.66%
Long-term debt, gross	$ 0	$ 343
Capital Lease Obligations
Debt Instrument [Line Items]
Capital lease obligations	$ 369	$ 282

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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