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Acquisitions Investments (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2020 | Dec. 31, 2021
Investment Holdings [Line Items] |  |  |
Equity Method Investment, Ownership Percentage | 100.00% | 100.00% |
Portion one of payments to acquire 22.4% of Huatai Group |  | $ 1,054 |
Huatai Group [Member] | CHINA |  |  |
Investment Holdings [Line Items] |  |  |
Equity Method Investment, Ownership Percentage | 46.20% | 46.20% |
Equity method investment, additional 15.3 ownership percentage obtained |  | 15.30% |
Portion one of payments to acquire 22.4% of Huatai Group | $ 1,100 | $ 1,054 |
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity | 1,300 | 1,300 |
Equity Method Investments | $ 2,400 | $ 2,400 |
Huatai Group [Member] | CHINA | Subsequent Event [Member] |  |  |
Investment Holdings [Line Items] |  |  |
Equity method investment, additional ownership agreed to be purchased |  |  | 22.40%
Amount agreed to acquire 22.4 percent of Huatai Group |  |  | $ 1,550
Equity method investment, additional 7.1 percentage obtained |  |  | 7.10%
Portion two of payments to acquire equity method investments |  |  | $ 493

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