FAIR VALUE ELECTIONS - Certain Structured and Non-Structured Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 135,000	$ 130,700
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	4,289	1,704
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	(124)	(134)
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	135,058	130,726
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	26,719	21,567
Interest rate linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	67,600	66,900
Foreign exchange linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	100	100
Equity linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	51,100	49,600
Commodity linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	8,900	7,000
Credit linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 7,300	$ 7,100

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- Definition

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

+ References

No definition available.

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- Definition

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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- Definition

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://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (d)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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