FAIR VALUE ELECTIONS - Certain Structured and Non-Structured Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 48,500	$ 49,700
Long-term debt
Certain non-structured liabilities
Aggregate unpaid principal balance in excess of (less than) fair value	(5,130)	(2,967)
Long-term debt \| Carrying amount
Certain non-structured liabilities
Carrying amount reported on the Consolidated Balance Sheet	67,063	55,783
Short-term borrowings
Certain non-structured liabilities
Aggregate unpaid principal balance in excess of (less than) fair value	68	1,411
Short-term borrowings \| Carrying amount
Certain non-structured liabilities
Carrying amount reported on the Consolidated Balance Sheet	4,683	4,946
Interest Rate Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	16,000	22,600
Foreign Exchange Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	1,200	700
Equity Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	27,300	23,700
Commodity Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	1,400	1,800
Credit Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 2,600	$ 900

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Fair value of financial and nonfinancial obligations.

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-Publisher FASB
-Name Accounting Standards Codification
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