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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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AOCI - Differences between Net Income and Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Condensed Statement of Income Captions [Line Items]
Net income (loss)	$ (1,157)			$ 659			$ (2,166)	$ 1,787
Other, net of deferred taxes	11			2			8	18
Total other comprehensive income (loss)	28			(93)			(41)	(83)
Comprehensive income (loss)	(1,129)	$ (859)	$ (219)	566	$ 675	$ 463	(2,207)	1,704
Other deferred taxes	3			0			2	4
Fuel derivatives
Condensed Statement of Income Captions [Line Items]
Unrealized gain (loss) on derivative instruments, net of deferred taxes	14			(80)			(20)	(61)
Derivative deferred taxes	5			(24)			(6)	(18)
Interest rate derivatives
Condensed Statement of Income Captions [Line Items]
Unrealized gain (loss) on derivative instruments, net of deferred taxes	3			(15)			(29)	(40)
Derivative deferred taxes	$ 0			$ (5)			$ (9)	$ (13)