LOANS - Non-accrual Corporate Loans (Details) - Corporate - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financing receivable impaired
Non-accrual corporate loans with specific allowances	$ 660	$ 1,437
Related specific allowance	302	362
Non-accrual corporate loans without specific allowances	717	445
Interest income	65	38	$ 66
Commercial and industrial
Financing receivable impaired
Non-accrual corporate loans with specific allowances	199	507
Related specific allowance	86	168
Non-accrual corporate loans without specific allowances	343	210
Mortgage and real estate
Financing receivable impaired
Non-accrual corporate loans with specific allowances	276	697
Related specific allowance	42	128
Non-accrual corporate loans without specific allowances	291	171
Lease financing
Financing receivable impaired
Non-accrual corporate loans without specific allowances	0	0
Other
Financing receivable impaired
Non-accrual corporate loans with specific allowances	185	185
Related specific allowance	174	51
Non-accrual corporate loans without specific allowances	10	61
Financial Institutions
Financing receivable impaired
Non-accrual corporate loans with specific allowances	0	48
Related specific allowance	0	15
Non-accrual corporate loans without specific allowances	$ 73	$ 3

Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Nonaccrual

No definition available.

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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

+ Details

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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

+ Details

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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

No definition available.

+ Details

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

+ Details

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- Details

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