Income Taxes (Schedule of Income Tax Provision (Benefit)) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current
US	$ (8)	$ (184)	$ 201
International	149	143	158
Total	141	(41)	359
Deferred
US	1	314	(110)
International	(18)	19	(36)
Total	(17)	333	(146)
Income tax provision (benefit)	$ 124	$ 292	$ 213

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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