FAIR VALUE ELECTIONS - Certain Structured and Non-Structured Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 50,900	$ 49,700
Long-term debt
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Aggregate unpaid principal balance in excess of (less than) fair value	(1,178)	(2,967)
Short-term borrowings
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Aggregate unpaid principal balance in excess of (less than) fair value	86	1,411
Carrying amount \| Long-term debt
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying amount reported on the consolidated balance sheet	63,056	55,783
Carrying amount \| Short-term borrowings
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying amount reported on the consolidated balance sheet	5,981	4,946
Interest rate linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	20,100	22,600
Foreign exchange linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	1,100	700
Equity linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	25,200	23,700
Commodity linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	2,000	1,800
Credit linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 2,500	$ 900

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+ References

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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.

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This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of long-term debt instruments that have contractual principal amounts and for which the fair value option has been elected.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
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Fair value of financial and nonfinancial obligations.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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