LOANS AND LEASES - Originated Troubled Debt Restructurings, Payment Default (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) Contract	Sep. 30, 2020 USD ($) Contract	Sep. 30, 2021 USD ($) Contract	Sep. 30, 2020 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	1	6	3	28
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 4
Total Commercial Loans and Leases [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	0	1	1	11
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 3
Total Commercial Loans and Leases [Member] \| Commercial Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract		0		8
Recorded Investment \| $		$ 0		$ 3
Total Commercial Loans and Leases [Member] \| Commercial and Industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	0	1	1	3
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0
Total Consumer Loan [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	1	5	2	17
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 1
Total Consumer Loan [Member] \| Direct Installment [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	1	4	1	12
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 1
Total Consumer Loan [Member] \| Residential Mortgages [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract	0	0	1	2
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0
Total Consumer Loan [Member] \| Consumer Lines of Credit [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| Contract		1		3
Recorded Investment \| $		$ 0		$ 0

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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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 http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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