Basis of Presentation and Significant Accounting Policies FX gain (loss) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Foreign Currency Transaction Gain (Loss), before Tax			$ 3	$ 13
Gain (Loss) on Investments [Member]
Foreign Currency Transaction Gain (Loss), before Tax	$ 1	$ 26	$ 3	$ 23

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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-Publisher FASB
-Name Accounting Standards Codification
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