DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Schedule of Derivative Activities Recorded in the Statement of Consolidated Operations (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Realized gain (loss):
Unrealized gain (loss)	$ 103	$ (59)	$ 0
Not Designated as Hedging Instrument
Realized gain (loss):
Derivative settlements, realized gain (loss)	(81)	24	0
Amortization of put premium, realized loss	(39)	(100)	0
Unrealized gain (loss)	103	(59)	0
Derivative instrument gains (losses), net	$ (17)	$ (135)	$ 0

Amortization Of Put Premium, Realized Gain (Loss)

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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