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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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
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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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LOANS - Corporate Loans (Details) $ in Millions	3 Months Ended		6 Months Ended
LOANS - Corporate Loans (Details) $ in Millions	Jun. 30, 2023 USD ($) category	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) category	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Receivables [Abstract]
Number of loan categories \| category	2		2
Loans
Loans, net of unearned income	$ 660,612		$ 660,612		$ 657,221
Lease financing
Loans
Loans, net of unearned income	300		300		400
Corporate
Loans
Loans sold and/or reclassified to held-for-sale	1,300	$ 1,100	2,900	$ 1,500
Loans, net of unearned income	286,021		286,021		289,154
Unearned income	(795)		(795)		(797)
Accrued interest receivable	2,000		2,000		2,000
Corporate \| Commercial and industrial
Loans
Loans, net of unearned income	152,591		152,591		147,803
Corporate \| Financial institutions
Loans
Loans, net of unearned income	57,594		57,594		64,907
Corporate \| Mortgage and real estate
Loans
Loans, net of unearned income	23,501		23,501		21,949
Corporate \| Lease financing
Loans
Loans, net of unearned income	273		273		354
Corporate \| In North America offices
Loans
Loans, net of unearned income	135,930		135,930		141,479
Corporate \| In North America offices \| Commercial and industrial
Loans
Loans, net of unearned income	59,790		59,790		56,176
Corporate \| In North America offices \| Financial institutions
Loans
Loans, net of unearned income	36,268		36,268		43,399
Corporate \| In North America offices \| Mortgage and real estate
Loans
Loans, net of unearned income	17,495		17,495		17,829
Corporate \| In North America offices \| Installment and other
Loans
Loans, net of unearned income	22,153		22,153		23,767
Corporate \| In North America offices \| Lease financing
Loans
Loans, net of unearned income	224		224		308
Corporate \| In offices outside North America
Loans
Loans, net of unearned income	150,091		150,091		147,675
Corporate \| In offices outside North America \| Commercial and industrial
Loans
Loans, net of unearned income	95,836		95,836		93,967
Corporate \| In offices outside North America \| Financial institutions
Loans
Loans, net of unearned income	21,701		21,701		21,931
Corporate \| In offices outside North America \| Mortgage and real estate
Loans
Loans, net of unearned income	6,076		6,076		4,179
Corporate \| In offices outside North America \| Installment and other
Loans
Loans, net of unearned income	23,395		23,395		23,347
Corporate \| In offices outside North America \| Lease financing
Loans
Loans, net of unearned income	49		49		46
Corporate \| In offices outside North America \| Government and official institutions
Loans
Loans, net of unearned income	$ 3,034		$ 3,034		$ 4,205