Acquisitions Investments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Mar. 31, 2020
Investment Holdings [Line Items]
Equity Method Investment, Ownership Percentage		100.00%
Huatai Group [Member]
Investment Holdings [Line Items]
Equity Method Investment, Ownership Percentage		30.90%
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 15.3 ownership percentage obtained	15.30%
Portion one of payments to acquire 22.4% of Huatai Group	$ 1,100
Equity method investment, additional 7.1 percentage obtained	7.10%
Portion two of payments to acquire equity method investments	$ 493
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions	53.30%

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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