CONTINGENCIES AND COMMITMENTS (Tax Matters and Tax Cuts and Jobs Act of 2017) (Details) $ in Millions	9 Months Ended
Sep. 30, 2018 USD ($)
Disaggregation of Revenue [Line Items]
Unrecognized tax benefits, decrease resulting from Settlements with taxing authorities	$ 10
Adjustment of provisional tax expense	12
Reduction to regulatory liability	$ 80

Tax Cuts And Jobs Act, Incomplete Accounting, Change In Tax Rate, Deferred Tax Liability, Provisional Income Tax Benefit

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- Definition

Tax Cuts And Jobs Act, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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