Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(d))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117546-209714

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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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Investments - Unrealized gains (losses) recognized in income (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Gain (Loss) on Securities [Line Items]
Debt Securities, Trading, Unrealized Gain (Loss)			$ 62	$ 169
Equity Securities, FV-NI, Unrealized Gain (Loss)			(20)	20
Consolidated Entity Excluding Variable Interest Entities (VIE)
Gain (Loss) on Securities [Line Items]
Debt Securities, Trading, Unrealized Gain (Loss)	$ 135	$ 98
Equity Securities, FV-NI, Unrealized Gain (Loss)	17	2
Related Party
Gain (Loss) on Securities [Line Items]
Debt Securities, Trading, Unrealized Gain (Loss)			(43)	(15)
Equity Securities, FV-NI, Unrealized Gain (Loss)			$ 0	$ (2)
Related Party \| Consolidated Entity Excluding Variable Interest Entities (VIE)
Gain (Loss) on Securities [Line Items]
Debt Securities, Trading, Unrealized Gain (Loss)	66	(13)
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ 0	$ (5)