VARIABLE INTEREST ENTITIES (Schedule of Consolidated Variable Interest Entities, Carrying Amounts of Assets and Liabilities) (Details) - USD ($) $ in Millions	Apr. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Pledged		$ 1,003	$ 975
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities		407	440
Variable Interest Entity, Primary Beneficiary [Member] | Cash and cash equivalents
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Current, Pledged		109	82
Variable Interest Entity, Primary Beneficiary [Member] | Other current assets
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Current, Pledged		116	114
Variable Interest Entity, Primary Beneficiary [Member] | Net property
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Noncurrent, Pledged		718	734
Variable Interest Entity, Primary Beneficiary [Member] | Other noncurrent assets
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Noncurrent, Pledged		60	45
Variable Interest Entity, Primary Beneficiary [Member] | Current liabilities
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Liabilities, Current		318	334
Variable Interest Entity, Primary Beneficiary [Member] | Long-term debt
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Liabilities, Noncurrent		43	75
Variable Interest Entity, Primary Beneficiary [Member] | Other noncurrent obligations
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Liabilities, Noncurrent		$ 46	$ 31
Subsequent Event [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Purchase Amount	$ 312