LOANS AND LEASES - Troubled Debt Restructurings (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) contract	Mar. 31, 2021 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	23	34
Pre- Modification Outstanding Recorded Investment	$ 1	$ 19
Post- Modification Outstanding Recorded Investment	$ 1	$ 19
Total commercial loans and leases
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	2	12
Pre- Modification Outstanding Recorded Investment	$ 0	$ 17
Post- Modification Outstanding Recorded Investment	$ 0	$ 17
Total commercial loans and leases \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	2	11
Pre- Modification Outstanding Recorded Investment	$ 0	$ 17
Post- Modification Outstanding Recorded Investment	$ 0	$ 17
Total commercial loans and leases \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract		1
Pre- Modification Outstanding Recorded Investment		$ 0
Post- Modification Outstanding Recorded Investment		$ 0
Total consumer loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	21	22
Pre- Modification Outstanding Recorded Investment	$ 1	$ 2
Post- Modification Outstanding Recorded Investment	$ 1	$ 2
Total consumer loans \| Direct installment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	13	10
Pre- Modification Outstanding Recorded Investment	$ 0	$ 0
Post- Modification Outstanding Recorded Investment	$ 0	$ 0
Total consumer loans \| Residential mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	5	2
Pre- Modification Outstanding Recorded Investment	$ 1	$ 1
Post- Modification Outstanding Recorded Investment	$ 1	$ 1
Total consumer loans \| Consumer lines of credit
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	3	10
Pre- Modification Outstanding Recorded Investment	$ 0	$ 1
Post- Modification Outstanding Recorded Investment	$ 0	$ 1

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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 http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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