REGULATORY MATTERS Schedule of Regulatory Assets and Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Schedule of Regulatory Assets and Liabilities [Line Items]
Current regulatory assets	$ 30	$ 12
Non-current regulatory assets	246	229
Current regulatory liabilities	(47)	(123)
Non-current regulatory liabilities	(587)	(584)
Net regulatory assets	56	3
Revenue Deferrals, Including Accrued Interest
Schedule of Regulatory Assets and Liabilities [Line Items]
Current regulatory liabilities	(27)	(51)
Non-current regulatory liabilities	(3)	(1)
Revenue Accruals, Including Accrued Interest
Schedule of Regulatory Assets and Liabilities [Line Items]
Current regulatory assets	28	12
Non-current regulatory assets	$ 58	$ 43

Net Regulatory Asset (Liability) Associated with Revenue Accruals and Deferrals

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- Definition

[Line Items] for Schedule of Regulatory Assets and Liabilities [Table]

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

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The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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