NOTES PAYABLE, LONG-TERM DEBT AND AVAILABLE CREDIT FACILITIES (Schedule of Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Unamortized debt discount and issuance costs	$ (331)	$ (334)
Long-term debt due within one year	(435)	(338)
Long-term debt	15,975	$ 19,253
Line of Credit Facility, Maximum Borrowing Capacity	9,428
Maturities of Long-term Debt [Abstract]
2020	435
2021	511
2022	1,513
2023	2,508
2024	1,528
Term Loan Facility 1
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 2,000
Promissory notes and debentures \| Final maturity 2019
Debt Instrument [Line Items]
Weighted average rate	0.00%	9.80%
Long-term debt, gross	$ 0	$ 7
Promissory notes and debentures \| Final maturity 2020
Debt Instrument [Line Items]
Weighted average rate	8.44%	4.46%
Long-term debt, gross	$ 76	$ 1,547
Promissory notes and debentures \| Final maturity 2021
Debt Instrument [Line Items]
Weighted average rate	8.95%	4.71%
Long-term debt, gross	$ 174	$ 1,424
Promissory notes and debentures \| Final maturity 2022
Debt Instrument [Line Items]
Weighted average rate	3.50%	3.50%
Long-term debt, gross	$ 1,372	$ 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
Debt Instrument [Line Items]
Weighted average rate	3.37%	3.50%
Long-term debt, gross	$ 1,397	$ 896
Promissory notes and debentures \| Final maturity 2025 and thereafter
Debt Instrument [Line Items]
Weighted average rate	5.70%	5.98%
Long-term debt, gross	$ 9,482	$ 7,963
Promissory notes and debentures \| U.S. dollar loans, various rates and maturities
Debt Instrument [Line Items]
Weighted average rate	2.55%	3.59%
Long-term debt, gross	$ 2,000	$ 4,533
Promissory notes and debentures \| Foreign currency loans, various rates and maturities
Debt Instrument [Line Items]
Weighted average rate	3.26%	3.20%
Long-term debt, gross	$ 592	$ 708
Medium-term notes, varying maturities through 2049
Debt Instrument [Line Items]
Weighted average rate	3.44%	3.26%
Long-term debt, gross	$ 928	$ 778
Finance Lease Obligations
Debt Instrument [Line Items]
Finance lease obligations	$ 395	$ 371

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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