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

Amount agreed to acquire 22.4 percent of Huatai Group

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The $493M cash outflow associated with the purchase of or advances to an equity method investments.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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