CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net Income/(Loss)	$ 372	$ (49)	$ 1,056	$ 281
Other Comprehensive (Loss)/Income
Unrealized gain/(loss) on derivatives, net	0	5	0	24
Foreign currency translation adjustments	(4)	(2)	(4)	(8)
Available-for-sale securities	(14)	0	(13)	1
Defined benefit plans	(41)	(1)	(47)	(3)
Other comprehensive (loss)/income	(59)	2	(64)	14
Comprehensive Income/(Loss)	313	(47)	992	295
Less: Comprehensive income attributable to noncontrolling interest and redeemable noncontrolling interest	0	26	1	15
Comprehensive Income (Loss), Net of Tax, Attributable to Parent, Total	$ 313	$ (73)	$ 991	$ 280

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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