Amount of unrealized gain (loss) on investment in debt and equity securities.

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- Definition

Fair value of obligations incurred from short sales.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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- Definition

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.

+ References

No definition available.

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Investments - Investment Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule of Investments [Line Items]
Investments	$ 9,897		$ 9,897		$ 8,913
Securities sold, not yet purchased, at fair value	4,957		4,957		2,521
Investment Segment
Schedule of Investments [Line Items]
Investments	9,653		9,653		8,239
Securities sold, not yet purchased, at fair value	4,957		4,957		2,521
Unrealized gain (loss) on debt and equity securities still held	(204)	$ (535)	1,384	$ (1,560)
Investment Segment \| Equity securities:
Schedule of Investments [Line Items]
Investments	9,537		9,537		8,118
Investment Segment \| Consumer, non-cyclical
Schedule of Investments [Line Items]
Investments	786		786		1,548
Securities sold, not yet purchased, at fair value	169		169		424
Investment Segment \| Consumer, cyclical
Schedule of Investments [Line Items]
Investments	1,732		1,732		2,073
Securities sold, not yet purchased, at fair value	713		713		572
Investment Segment \| Energy
Schedule of Investments [Line Items]
Investments	3,153		3,153		2,654
Securities sold, not yet purchased, at fair value	2,112		2,112		1,476
Investment Segment \| Utilities
Schedule of Investments [Line Items]
Investments	761		761		107
Securities sold, not yet purchased, at fair value	588		588		49
Investment Segment \| Healthcare
Schedule of Investments [Line Items]
Investments	950		950
Securities sold, not yet purchased, at fair value	969		969
Investment Segment \| Technology
Schedule of Investments [Line Items]
Investments	1,715		1,715		1,578
Investment Segment \| Materials
Schedule of Investments [Line Items]
Investments	181		181
Securities sold, not yet purchased, at fair value	321		321
Investment Segment \| Industrial
Schedule of Investments [Line Items]
Investments	259		259		158
Investment Segment \| Other
Schedule of Investments [Line Items]
Securities sold, not yet purchased, at fair value	85		85
Investment Segment \| Corporate debt securities
Schedule of Investments [Line Items]
Investments	$ 116		$ 116		$ 121