DERIVATIVES - Effect of Customer Derivatives and Economic Hedges on Net Income (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ 27	$ 23
Economic hedges \| Customer interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ 34	$ (767)
Derivative, gain (loss), statement of income or comprehensive income	Foreign exchange and derivative products	Foreign exchange and derivative products
Economic hedges \| Derivatives hedging interest rate risk
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ (19)	$ 793
Derivative, gain (loss), statement of income or comprehensive income	Foreign exchange and derivative products	Foreign exchange and derivative products
Economic hedges \| Customer foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ (4)	$ 26
Derivative, gain (loss), statement of income or comprehensive income	Foreign exchange and derivative products	Foreign exchange and derivative products
Economic hedges \| Derivatives hedging foreign exchange risk
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ (2)	$ 3
Derivative, gain (loss), statement of income or comprehensive income	Foreign exchange and derivative products	Foreign exchange and derivative products
Economic hedges \| Customer commodity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ (475)	$ 1,152
Derivative, gain (loss), statement of income or comprehensive income	Foreign exchange and derivative products	Foreign exchange and derivative products
Economic hedges \| Derivatives hedging commodity price risk
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ 486	$ (1,148)
Derivative, gain (loss), statement of income or comprehensive income	Foreign exchange and derivative products	Foreign exchange and derivative products
Economic hedges \| Residential loan commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ 2	$ (161)
Derivative, gain (loss), statement of income or comprehensive income	Mortgage banking fees	Mortgage banking fees
Economic hedges \| Derivatives hedging residential loan commitments and mortgage loans held for sale, at fair value
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ (11)	$ 271
Derivative, gain (loss), statement of income or comprehensive income	Mortgage banking fees	Mortgage banking fees
Economic hedges \| Derivative contracts used to hedge residential MSRs
Derivative Instruments, Gain (Loss) [Line Items]
Amounts recognized in noninterest income	$ 16	$ (146)
Derivative, gain (loss), statement of income or comprehensive income	Mortgage banking fees	Mortgage banking fees

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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