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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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LOANS - Corporate Loan Modifications to Borrowers Experiencing Financial Difficulty (Details) - Corporate - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Financing receivable impaired
Total modifications balance	$ 369
Term extension
Financing receivable impaired
Total modifications balance	369
Combination: term extension and payment delay
Financing receivable impaired
Total modifications balance	0
Commercial and industrial
Financing receivable impaired
Total modifications balance	$ 286
Weighted- average term extension (months)	14 months
Commercial and industrial \| Term extension
Financing receivable impaired
Total modifications balance	$ 286
Commercial and industrial \| Combination: term extension and payment delay
Financing receivable impaired
Total modifications balance	0
Commercial and industrial \| Combination: Term extension and payment delay
Financing receivable impaired
Weighted- average term extension (months)		16 months
Financial institutions
Financing receivable impaired
Total modifications balance	0
Financial institutions \| Term extension
Financing receivable impaired
Total modifications balance	0
Financial institutions \| Combination: term extension and payment delay
Financing receivable impaired
Total modifications balance	0
Mortgage and real estate
Financing receivable impaired
Total modifications balance	77
Mortgage and real estate \| Term extension
Financing receivable impaired
Total modifications balance	77
Mortgage and real estate \| Combination: term extension and payment delay
Financing receivable impaired
Total modifications balance	$ 0
Mortgage and real estate \| Combination: Term extension and payment delay
Financing receivable impaired
Weighted- average term extension (months)	40 months	18 months
Other
Financing receivable impaired
Total modifications balance	$ 6
Weighted- average term extension (months)	49 months
Other \| Term extension
Financing receivable impaired
Total modifications balance	$ 6
Other \| Combination: term extension and payment delay
Financing receivable impaired
Total modifications balance	$ 0