The number of loan categories reported by the entity.

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Total amount of portfolio loans sold and or reclassified to loans held-for-sale during the period.

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Amount, after allowance for credit loss, of accrued interest on financing receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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Amount of fee received for commitment to originate or purchase financing receivable where likelihood of commitment being exercised is remote, to be recognized as service income.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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LOANS - Corporate Loans (Details) $ in Millions	3 Months Ended
LOANS - Corporate Loans (Details) $ in Millions	Mar. 31, 2023 USD ($) category	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Loans and Leases Receivable Disclosure [Abstract]
Number of loan categories \| category	2
Loans
Loans, net of unearned income	$ 651,995		$ 657,221
Lease financing
Loans
Loans, net of unearned income	300		400
Corporate
Loans
Loans sold and/or reclassified to held-for-sale	900	$ 300
Loans, net of unearned income	288,299		289,154
Unearned income	(801)		(797)
Accrued interest receivable	2,000		2,000
Corporate \| Commercial and industrial
Loans
Loans, net of unearned income	150,330		147,803
Corporate \| Financial institutions
Loans
Loans, net of unearned income	60,434		64,907
Corporate \| Mortgage and real estate
Loans
Loans, net of unearned income	23,478		21,949
Corporate \| Lease financing
Loans
Loans, net of unearned income	348		354
Corporate \| In North America offices
Loans
Loans, net of unearned income	140,753		141,479
Corporate \| In North America offices \| Commercial and industrial
Loans
Loans, net of unearned income	59,790		56,176
Corporate \| In North America offices \| Financial institutions
Loans
Loans, net of unearned income	38,524		43,399
Corporate \| In North America offices \| Mortgage and real estate
Loans
Loans, net of unearned income	18,562		17,829
Corporate \| In North America offices \| Installment and other
Loans
Loans, net of unearned income	23,578		23,767
Corporate \| In North America offices \| Lease financing
Loans
Loans, net of unearned income	299		308
Corporate \| In offices outside North America
Loans
Loans, net of unearned income	147,546		147,675
Corporate \| In offices outside North America \| Commercial and industrial
Loans
Loans, net of unearned income	92,803		93,967
Corporate \| In offices outside North America \| Financial institutions
Loans
Loans, net of unearned income	22,272		21,931
Corporate \| In offices outside North America \| Mortgage and real estate
Loans
Loans, net of unearned income	4,975		4,179
Corporate \| In offices outside North America \| Installment and other
Loans
Loans, net of unearned income	24,800		23,347
Corporate \| In offices outside North America \| Lease financing
Loans
Loans, net of unearned income	49		46
Corporate \| In offices outside North America \| Government and official institutions
Loans
Loans, net of unearned income	$ 2,647		$ 4,205