FAIR VALUE ELECTIONS - Certain Structured and Non-Structured Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 35,700	$ 29,300
Long-term debt
Certain non-structured liabilities
Aggregate unpaid principal balance in excess of (less than) fair value	3,814	(579)
Long-term debt \| Carrying amount
Certain non-structured liabilities
Carrying amount reported on the Consolidated Balance Sheet	38,229	31,392
Short-term borrowings
Certain non-structured liabilities
Aggregate unpaid principal balance in excess of (less than) fair value	861	74
Short-term borrowings \| Carrying amount
Certain non-structured liabilities
Carrying amount reported on the Consolidated Balance Sheet	4,483	4,627
Interest Rate Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	17,300	13,900
Foreign Exchange Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	500	300
Equity Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	14,800	13,000
Commodity Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	1,200	200
Credit Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 1,900	$ 1,900

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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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