LOANS - Consumer Loans - Classifiably Managed (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	$ 793,658	$ 752,230
Investment grade %	69.00%
Unallocated portfolio layer cumulative basis adjustments		17
Total	$ 416,622
Consumer loans
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	416,520	408,533
Unallocated portfolio layer cumulative basis adjustments	(102)	343
Classifiably managed \| Consumer loans
Financing Receivable, Modified [Line Items]
Total	53,504
Delinquency-managed loans \| Consumer loans
Financing Receivable, Modified [Line Items]
Total	363,118
In North America offices \| Consumer loans
Financing Receivable, Modified [Line Items]
Loans, net of unearned income		329,128
Total	334,463
In North America offices \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	120,516	119,389
In North America offices \| Consumer loans \| Home equity loans
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	2,271	2,872
In North America offices \| Consumer loans \| Total credit cards
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	177,608	173,656
In North America offices \| Consumer loans \| Personal, small business and other
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	34,068	33,211
In North America offices \| Classifiably managed \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	0
In North America offices \| Classifiably managed \| Consumer loans \| Home equity loans
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	0
In North America offices \| Classifiably managed \| Consumer loans \| Total credit cards
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	0
In North America offices \| Classifiably managed \| Consumer loans \| Personal, small business and other
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	$ 27,482
Investment grade %	80.00%
In North America offices \| Delinquency-managed loans \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	$ 120,516
In North America offices \| Delinquency-managed loans \| Consumer loans \| Home equity loans
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	2,271
In North America offices \| Delinquency-managed loans \| Consumer loans \| Total credit cards
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	177,608
In North America offices \| Delinquency-managed loans \| Consumer loans \| Personal, small business and other
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	6,586
In offices outside North America \| Consumer loans
Financing Receivable, Modified [Line Items]
Loans, net of unearned income		79,062
Total	82,159
In offices outside North America \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	23,866	24,041
In offices outside North America \| Consumer loans \| Total credit cards
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	14,814	14,701
In offices outside North America \| Consumer loans \| Personal, small business and other
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	43,479	40,320
In offices outside North America \| Classifiably managed \| Consumer loans
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	26,022	22,297
In offices outside North America \| Classifiably managed \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	0	0
In offices outside North America \| Classifiably managed \| Consumer loans \| Total credit cards
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	0	0
In offices outside North America \| Classifiably managed \| Consumer loans \| Personal, small business and other
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	$ 26,022	22,297
Investment grade %	58.00%
In offices outside North America \| Delinquency-managed loans \| Consumer loans
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	$ 56,137	56,765
In offices outside North America \| Delinquency-managed loans \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	23,866	24,041
In offices outside North America \| Delinquency-managed loans \| Consumer loans \| Total credit cards
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	14,814	14,701
In offices outside North America \| Delinquency-managed loans \| Consumer loans \| Personal, small business and other
Financing Receivable, Modified [Line Items]
Loans, net of unearned income	$ 17,457	$ 18,023

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, in portfolio layer hedging relationship.

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