Earnings Per Share Net Income for Earnings Per Share Calculations - Basic and Diluted (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share [Abstract]
Income from continuing operations after income taxes	$ 766	$ 483	$ 1,047	$ 299	[1]
Net income Attributable to Noncontrolling Interest, Continuing Operations	6	13	16	21
Net income from Continuing Operations Available to Common Shareholders	760	470	1,031	278
Income (loss) from discontinued operations after income taxes	0	(1,077)	1	(717)
Income from Discontinued Operations, Attributable to Noncontrolling Interest	0	1	0	5
Net (Loss) Income from Discontinued Operations Available to Common Shareholders	0	(1,078)	1	(722)
Net income (loss) Available to Common Stockholders	$ 760	$ (608)	$ 1,032	$ (444)

[1] Period is presented on a pro forma basis, prepared in accordance with Article 11 of Regulation S-X.