LOANS AND LEASES - Troubled Debt Restructurings (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($) contract	Sep. 30, 2021 USD ($) contract	Sep. 30, 2022 USD ($) contract	Sep. 30, 2021 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	33	36	103	102
Pre- Modification Outstanding Recorded Investment	$ 3	$ 4	$ 13	$ 26
Post- Modification Outstanding Recorded Investment	$ 3	$ 4	$ 12	$ 25
Total commercial loans and leases
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	5	9	24	30
Pre- Modification Outstanding Recorded Investment	$ 0	$ 2	$ 6	$ 21
Post- Modification Outstanding Recorded Investment	$ 0	$ 2	$ 5	$ 20
Total commercial loans and leases \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	2	5	14	21
Pre- Modification Outstanding Recorded Investment	$ 0	$ 2	$ 5	$ 20
Post- Modification Outstanding Recorded Investment	$ 0	$ 2	$ 4	$ 20
Total commercial loans and leases \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	3	3	10	8
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 1	$ 1
Post- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 1	$ 0
Total commercial loans and leases \| Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract		1		1
Pre- Modification Outstanding Recorded Investment		$ 0		$ 0
Post- Modification Outstanding Recorded Investment		$ 0		$ 0
Total consumer loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	28	27	79	72
Pre- Modification Outstanding Recorded Investment	$ 3	$ 2	$ 7	$ 5
Post- Modification Outstanding Recorded Investment	$ 3	$ 2	$ 7	$ 5
Total consumer loans \| Direct installment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	8	8	33	26
Pre- Modification Outstanding Recorded Investment	$ 1	$ 0	$ 1	$ 1
Post- Modification Outstanding Recorded Investment	$ 1	$ 0	$ 1	$ 1
Total consumer loans \| Residential mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	14	12	34	15
Pre- Modification Outstanding Recorded Investment	$ 2	$ 2	$ 5	$ 2
Post- Modification Outstanding Recorded Investment	$ 2	$ 2	$ 5	$ 2
Total consumer loans \| Consumer lines of credit
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	6	7	12	31
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 1	$ 2
Post- Modification Outstanding Recorded Investment	$ 0	$ 0	$ 1	$ 2

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Number of financing receivables that have been modified by troubled debt restructurings.

+ 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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