Income Taxes (Schedule of Income Tax Provision (Benefit)) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current
US	$ 13	$ (8)	$ (184)
International	126	149	143
Total	139	141	(41)
Deferred
US	308	1	314
International	(200)	(18)	19
Total	108	(17)	333
Income tax provision (benefit)	$ 247	$ 124	$ 292

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