FAIR VALUE ELECTIONS - Certain Structured and Non-Structured Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 78,200	$ 67,000
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	(3,019)	(5,130)
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	0	68
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	78,178	67,063
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	8,814	4,683
Interest rate linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	38,300	34,500
Foreign exchange linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	200	1,200
Equity linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	32,800	27,300
Commodity linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	4,000	1,400
Credit linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 2,900	$ 2,600

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+ References

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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
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-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
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