Fair Value Measurements - Fair Value Measurement (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Assets [Abstract]
Derivative contracts, at fair value (asset)	$ 900	$ 612
Liabilities [Abstract]
Securities sold, not yet purchased, at fair value	4,062	5,340
Derivative contracts, at fair value (liability)	822	787
Recurring measurement
Assets [Abstract]
Investments	5,723	9,060
Derivative contracts, at fair value (asset)	896	612
Assets, Fair Value Disclosure	6,619	9,672
Liabilities [Abstract]
Securities sold, not yet purchased, at fair value	4,062	5,340
Derivative contracts, at fair value (liability)	822	787
Other liabilities	708	494
Financial and Nonfinancial Liabilities, Fair Value Disclosure	5,592	6,621
Recurring measurement \| Level 1
Assets [Abstract]
Investments	5,645	8,905
Assets, Fair Value Disclosure	5,645	8,905
Liabilities [Abstract]
Securities sold, not yet purchased, at fair value	4,062	5,340
Financial and Nonfinancial Liabilities, Fair Value Disclosure	4,062	5,340
Recurring measurement \| Level 2
Assets [Abstract]
Investments	36	113
Derivative contracts, at fair value (asset)	896	612
Assets, Fair Value Disclosure	932	725
Liabilities [Abstract]
Derivative contracts, at fair value (liability)	822	787
Other liabilities	708	494
Financial and Nonfinancial Liabilities, Fair Value Disclosure	1,530	1,281
Recurring measurement \| Level 3
Assets [Abstract]
Investments	42	42
Assets, Fair Value Disclosure	$ 42	$ 42

Investments measured at fair value

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- Definition

Unrealized Gain On Derivative Contracts.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Section 50
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- Definition

Fair value of obligations incurred from short sales.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Fair value of financial and nonfinancial obligations.

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- Definition

Fair value portion of other liabilities.

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