Earnings Per Share Net Income for Earnings Per Share Calculations - Basic and Diluted (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Income (loss) from continuing operations after income taxes	$ (390)	$ (527)	$ 657	$ (228)
Net income (loss) Attributable to Noncontrolling Interest, Continuing Operations	2	(11)	18	10
Net income (loss) from Continuing Operations Available to Common Shareholders	(392)	(516)	639	(238)
Income (loss) from discontinued operations after income taxes	0	22	1	(695)
Income from Discontinued Operations, Attributable to Noncontrolling Interest	0	0	0	5
Net (Loss) Income from Discontinued Operations Available to Common Shareholders	0	22	1	(700)
Net income (loss) Available to Common Stockholders	$ (392)	$ (494)	$ 640	$ (938)

Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

Amount after tax of income (loss) from a discontinued operation attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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+ Details