VARIABLE INTEREST ENTITIES (Schedule of Consolidated Variable Interest Entities, Carrying Amounts of Assets and Liabilities) (Details) - Variable Interest Entity, Primary Beneficiary [Member] - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Pledged	$ 1,189	$ 1,195
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	560	593
Cash and cash equivalents
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Current, Pledged	140	107	$ 140	$ 107
Other current assets
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Current, Pledged	129	131
Net property
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Noncurrent, Pledged	869	907	$ 869	$ 907
Other noncurrent assets
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Noncurrent, Pledged	51	50
Current liabilities
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Liabilities, Current	296	303
Current liabilities | Variable Interest Entities Used to Monetize Accounts Receivable [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Liabilities, Current	1	1
Variable Interest Entity, Consolidated, Liabilities, Current, No Recourse	0	0
Long-term debt
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Liabilities, Noncurrent	225	249
Other noncurrent obligations
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Liabilities, Noncurrent	39	41
Current Assets [Member] | Variable Interest Entities Used to Monetize Accounts Receivable [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Assets, Current	9	671
Variable Interest Entity, Consolidated, Assets, Current, Pledged	$ 0	$ 0