LOANS - Corporate Troubled Debt Restructurings (Details) - Corporate - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Financing receivable impaired
Troubled debt restructurings	$ 93	$ 92
Period within which default occurred post-modification	1 year
Number of days past due, default status	60 days
TDR balances	$ 110	284
TDR in payment default	$ 0	0
Commercial banking
Financing receivable impaired
Number of days past due, default status	90 days
Commercial and industrial
Financing receivable impaired
Troubled debt restructurings	$ 61	82
TDR balances	85	236
TDR in payment default	0	0
Mortgage and real estate
Financing receivable impaired
Troubled debt restructurings	2	4
TDR balances	13	20
TDR in payment default	0	0
Other
Financing receivable impaired
Troubled debt restructurings	30	6
TDR balances	12	28
TDR in payment default	0	0
TDRs involving changes in the amount and/or timing of principal payments
Financing receivable impaired
Troubled debt restructurings	1	0
TDRs involving changes in the amount and/or timing of principal payments \| Commercial and industrial
Financing receivable impaired
Troubled debt restructurings	0	0
TDRs involving changes in the amount and/or timing of principal payments \| Mortgage and real estate
Financing receivable impaired
Troubled debt restructurings	1	0
TDRs involving changes in the amount and/or timing of principal payments \| Other
Financing receivable impaired
Troubled debt restructurings	0	0
TDRs involving vhanges in the amount and/or timing of interest payments
Financing receivable impaired
Troubled debt restructurings	0	0
TDRs involving vhanges in the amount and/or timing of interest payments \| Commercial and industrial
Financing receivable impaired
Troubled debt restructurings	0	0
TDRs involving vhanges in the amount and/or timing of interest payments \| Mortgage and real estate
Financing receivable impaired
Troubled debt restructurings	0	0
TDRs involving vhanges in the amount and/or timing of interest payments \| Other
Financing receivable impaired
Troubled debt restructurings
TDRs invovling changes in the amount and/or timing of both principal and interest payments
Financing receivable impaired
Troubled debt restructurings	92	92
TDRs invovling changes in the amount and/or timing of both principal and interest payments \| Commercial and industrial
Financing receivable impaired
Troubled debt restructurings	61	82
TDRs invovling changes in the amount and/or timing of both principal and interest payments \| Mortgage and real estate
Financing receivable impaired
Troubled debt restructurings	1	4
TDRs invovling changes in the amount and/or timing of both principal and interest payments \| Other
Financing receivable impaired
Troubled debt restructurings	$ 30	$ 6

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Represents the classified default number of days for which the loan is past due.

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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