LOANS - Non-accrual Corporate Loans (Details) - Corporate - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Financing receivable impaired
Non-accrual corporate loans with specific allowances	$ 953	$ 660
Related specific allowance	323	302
Non-accrual corporate loans without specific allowances	1,048	717
Interest income	35	65	$ 38
Commercial and industrial
Financing receivable impaired
Non-accrual corporate loans with specific allowances	788	199
Related specific allowance	295	86
Non-accrual corporate loans without specific allowances	353	343
Mortgage and real estate
Financing receivable impaired
Non-accrual corporate loans with specific allowances	44	276
Related specific allowance	4	42
Non-accrual corporate loans without specific allowances	583	291
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	121	185
Related specific allowance	24	174
Non-accrual corporate loans without specific allowances	47	10
Financial Institutions
Financing receivable impaired
Non-accrual corporate loans with specific allowances	0	0
Related specific allowance	0	0
Non-accrual corporate loans without specific allowances	$ 65	$ 73

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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