DERIVATIVES - Effect of Customer Derivatives and Economic Hedges on Net Income (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	$ 153	$ 112	$ (72)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Fees and Commissions, Mortgage Banking and Servicing, Foreign exchange and derivative products	Fees and Commissions, Mortgage Banking and Servicing, Foreign exchange and derivative products	Fees and Commissions, Mortgage Banking and Servicing, Foreign exchange and derivative products
Economic hedges \| Customer interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	$ (505)	$ (2,027)	$ (374)
Economic hedges \| Derivatives hedging interest rate risk
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	551	2,090	401
Economic hedges \| Customer foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	94	(180)	(207)
Economic hedges \| Derivatives hedging foreign exchange risk
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	14	313	305
Economic hedges \| Customer commodity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	(900)	1,121	779
Economic hedges \| Derivatives hedging commodity price risk
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	941	(1,097)	(770)
Economic hedges \| Residential loan commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	(34)	(284)	(208)
Economic hedges \| Derivatives hedging residential loan commitments and mortgage LHFS, at fair value
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	25	489	152
Economic hedges \| Derivative contracts used to hedge residential MSRs
Derivative Instruments, Gain (Loss) [Line Items]
Amounts Recognized in Noninterest Income	$ (33)	$ (313)	$ (150)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4E

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