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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 Troubled Debt Restructurings (Details) - Corporate - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Financing receivable impaired
Troubled debt restructurings		$ 356
TDR in payment default	$ 7	0
Commitments to lend	$ 418	878
Commercial and industrial
Financing receivable impaired
Troubled debt restructurings		251
Weighted- average term extension (months)	14 months
Financial institutions
Financing receivable impaired
Troubled debt restructurings		0
Mortgage and real estate
Financing receivable impaired
Troubled debt restructurings		105
Other
Financing receivable impaired
Troubled debt restructurings		0
Weighted- average term extension (months)	49 months
TDRs involving changes in the amount and/or timing of principal payments
Financing receivable impaired
Troubled debt restructurings		356
TDRs involving changes in the amount and/or timing of principal payments \| Commercial and industrial
Financing receivable impaired
Troubled debt restructurings		251
TDRs involving changes in the amount and/or timing of principal payments \| Financial institutions
Financing receivable impaired
Troubled debt restructurings		0
TDRs involving changes in the amount and/or timing of principal payments \| Mortgage and real estate
Financing receivable impaired
Troubled debt restructurings		105
TDRs involving changes in the amount and/or timing of principal payments \| Other
Financing receivable impaired
Troubled debt restructurings		0
TDRs involving vhanges in the amount and/or timing of interest payments
Financing receivable impaired
Troubled debt restructurings		0
TDRs involving vhanges in the amount and/or timing of interest payments \| Commercial and industrial
Financing receivable impaired
Troubled debt restructurings		0
TDRs involving vhanges in the amount and/or timing of interest payments \| Financial institutions
Financing receivable impaired
Troubled debt restructurings		0
TDRs involving vhanges in the amount and/or timing of interest payments \| Mortgage and real estate
Financing receivable impaired
Troubled debt restructurings		0
TDRs involving vhanges in the amount and/or timing of interest payments \| Other
Financing receivable impaired
Troubled debt restructurings		$ 0
Combination: Term extension and payment delay \| Commercial and industrial
Financing receivable impaired
Weighted- average term extension (months)		16 months
Combination: Term extension and payment delay \| Mortgage and real estate
Financing receivable impaired
Weighted- average term extension (months)	40 months	18 months