NOTES PAYABLE, LONG-TERM DEBT AND AVAILABLE CREDIT FACILITIES (Schedule of Long-Term Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Unamortized debt discount and issuance costs	$ (337)	$ (346)
Long-term debt due within one year	920	752
Long-term debt	(19,596)	$ (19,765)
Annual Installments on Long Term Debt for Next Five Years at the current period end [Abstract]
Annual Installments on Long Term Debt, 2018	809
Annual Installments on Long Term Debt, 2019	6,932
Annual Installments on Long Term Debt, 2020	1,834
Annual Installments on Long Term Debt, 2021	1,575
Annual Installments on Long Term Debt, 2022	1,496
Annual Installments on Long Term Debt, 2023	$ 469
Loans Payable [Member] \| Promissory Notes and Debentures, Final Maturity, Current Year [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	5.78%	5.78%
Long-term Debt, Gross	$ 339	$ 339
Loans Payable [Member] \| Promissory Notes and Debentures, Final Maturity, Year One [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	8.55%	8.55%
Long-term Debt, Gross	$ 2,122	$ 2,122
Loans Payable [Member] \| Promissory Notes and Debentures, Final Maturity, Year Two [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	4.46%	4.46%
Long-term Debt, Gross	$ 1,547	$ 1,547
Loans Payable [Member] \| Promissory Notes and Debentures, Final Maturity, Year Three [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	4.71%	4.71%
Long-term Debt, Gross	$ 1,424	$ 1,424
Loans Payable [Member] \| Promissory Notes and Debentures, Final Maturity, Year Four [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	3.50%	3.50%
Long-term Debt, Gross	$ 1,373	$ 1,373
Loans Payable [Member] \| Promissory Notes and Debentures, Final Maturity, Year Five [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	7.64%	7.64%
Long-term Debt, Gross	$ 325	$ 325
Loans Payable [Member] \| Promissory Notes and Debentures, Final Maturity, Year Six and Thereafter [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	5.92%	5.92%
Long-term Debt, Gross	$ 6,857	$ 6,857
Loans Payable [Member] \| U.S. Dollar Loans [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	2.89%	2.44%
Long-term Debt, Gross	$ 4,564	$ 4,564
Loans Payable [Member] \| Foreign Currency Loans [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	3.00%	3.00%
Long-term Debt, Gross	$ 841	$ 814
Medium-term Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	3.23%	3.20%
Long-term Debt, Gross	$ 853	$ 873
Tax-Exempt Bonds [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	5.69%	5.66%
Long-term Debt, Gross	$ 328	$ 343
Tax-Exempt Bonds [Member] \| Five Point Nine Percent Tax-Exempt Bonds due 2038 [Member]
Debt Instrument [Line Items]
Debt Instrument, Notice to Call	75
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Capital Lease Obligations	$ 280	$ 282
Tax-Exempt Bonds [Member] \| Tax-Exempt Bonds [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	5.90%

Face (par) amount of the original debt instrument that will be repurchased.

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