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

No definition available.

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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
-SubTopic 320
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35711043&loc=d3e42429-110968

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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
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(h))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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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
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Schedule of Investments [Line Items]
Investments	$ 8,197		$ 9,945
Securities sold, not yet purchased, at fair value	459		1,190
Investment Segment
Schedule of Investments [Line Items]
Investments	7,519		9,207
Securities sold, not yet purchased, at fair value	459		1,190
Unrealized gain (loss) on debt and equity securities still held	(4,170)	$ 558
Investment Segment \| Equity securities:
Schedule of Investments [Line Items]
Investments	7,420		9,062
Investment Segment \| Basic materials
Schedule of Investments [Line Items]
Investments	181		281
Securities sold, not yet purchased, at fair value	23		209
Investment Segment \| Consumer, non-cyclical
Schedule of Investments [Line Items]
Investments	1,478		2,085
Securities sold, not yet purchased, at fair value			29
Investment Segment \| Consumer, cyclical
Schedule of Investments [Line Items]
Investments	1,881		2,427
Securities sold, not yet purchased, at fair value	188		379
Investment Segment \| Energy
Schedule of Investments [Line Items]
Investments	1,758		1,717
Securities sold, not yet purchased, at fair value			124
Investment Segment \| Financial
Schedule of Investments [Line Items]
Securities sold, not yet purchased, at fair value	84		152
Investment Segment \| Technology
Schedule of Investments [Line Items]
Investments	2,061		2,425
Securities sold, not yet purchased, at fair value	138		217
Investment Segment \| Industrial
Schedule of Investments [Line Items]
Investments	61		127
Investment Segment \| Communication
Schedule of Investments [Line Items]
Securities sold, not yet purchased, at fair value	26		80
Investment Segment \| Corporate debt securities
Schedule of Investments [Line Items]
Investments	$ 99		$ 145