Income Taxes (Schedule of Income Tax Provision (Benefit)) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current
US	$ (184)	$ 201	$ (22)
International	143	158	60
Total	(41)	359	38
Deferred
US	314	(110)	108
International	19	(36)	(24)
Total	333	(146)	84
Income tax provision (benefit)	$ 292	$ 213	$ 122

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

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