Description of Business and Accounting Policies - Other Income (Expense), Net (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Foreign currency gains (losses)	$ (20)	$ (206)	$ 247
Derivative [Line Items]
Equity Securities Gains	231	145	18
Equity Warrant
Derivative [Line Items]
Derivative gains (losses)	$ 11	$ (131)	$ 109

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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-Section 50
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