Fair Value of Equity Method Investment Under Fair Value Option

No definition available.

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- Definition

Unrealized gain (loss) on equity method investments under fair value option

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

Fair value of obligations incurred from short sales.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-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=6879938&loc=d3e572229-122910

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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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- Definition

Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82895926&loc=d3e24584-111560

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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Investments and Related Matters Investment Segment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Investments [Line Items]
Investments	$ 10,369	$ 9,881
Securities sold, not yet purchased, at fair value	1,023	1,139
Investment Segment
Schedule of Investments [Line Items]
Investments	9,532	9,213
Securities sold, not yet purchased, at fair value	1,023	1,139
Portion of trading (losses) gains that relates to trading securities still held at balance sheet date	1,413	340	$ (2,222)
Investment Segment \| Equity securities
Schedule of Investments [Line Items]
Investments	9,377	9,023
Securities sold, not yet purchased, at fair value	988	1,087
Investment Segment \| Debt securities
Schedule of Investments [Line Items]
Investments	155	190
Basic materials \| Investment Segment \| Equity securities
Schedule of Investments [Line Items]
Investments	1,170	963
Consumer, non-cyclical \| Investment Segment \| Equity securities
Schedule of Investments [Line Items]
Investments	2,551	2,677
Securities sold, not yet purchased, at fair value	101	0
Consumer, cyclical \| Investment Segment \| Equity securities
Schedule of Investments [Line Items]
Securities sold, not yet purchased, at fair value	667	968
Consumer, cyclical \| Investment Segment \| Debt securities
Schedule of Investments [Line Items]
Securities sold, not yet purchased, at fair value	35	52
Energy \| Investment Segment \| Equity securities
Schedule of Investments [Line Items]
Investments	1,489	1,278
Securities sold, not yet purchased, at fair value	110	19
Financial \| Investment Segment \| Equity securities
Schedule of Investments [Line Items]
Investments	2,185	2,385
Industrial \| Investment Segment \| Equity securities
Schedule of Investments [Line Items]
Securities sold, not yet purchased, at fair value	110	100
Technology \| Investment Segment \| Equity securities
Schedule of Investments [Line Items]
Investments	833	911
Other sectors \| Investment Segment \| Equity securities
Schedule of Investments [Line Items]
Investments	$ 1,149	809
Herbalife \| Investment Segment
Schedule of Investments [Line Items]
Ownership percentage in equity method investment	21.00%
Unrealized gain on equity method investments under fair value option	$ 357	(113)
Fair Value of Equity Method Investment Under Fair Value Option	$ 1,200	867
Hertz \| Investment Segment
Schedule of Investments [Line Items]
Ownership percentage in equity method investment	28.00%
Unrealized gain on equity method investments under fair value option	$ 13	(389)
Fair Value of Equity Method Investment Under Fair Value Option	$ 517	$ 505