LOANS AND LEASES - Schedule of Financial Effects of Loans Modified (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	12 months	13 months	15 months	15 months
Weighted Average Interest Rate Reduction	1.04%	0.71%	1.38%	0.95%
Weighted Average Payment Delay (in Months)	13 months	11 months	10 months	10 months
Loan modifications			$ 1	$ 1
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	12 months	13 months	15 months	15 months
Weighted Average Interest Rate Reduction	0.84%	0.65%	1.35%	0.91%
Weighted Average Payment Delay (in Months)	14 months	11 months	10 months	10 months
Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	14 months	15 months	20 months	15 months
Weighted Average Interest Rate Reduction	2.85%	1.05%	0.88%	1.31%
Weighted Average Payment Delay (in Months)	20 months	12 months	13 months	12 months
Commercial \| Owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	13 months	0 months	10 months	11 months
Weighted Average Interest Rate Reduction	0.23%	0.00%	1.72%	1.93%
Weighted Average Payment Delay (in Months)	3 months	6 months	6 months	5 months
Commercial \| Investor dependent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	12 months	13 months	9 months	9 months
Weighted Average Interest Rate Reduction	0.00%	0.00%	0.00%	0.00%
Weighted Average Payment Delay (in Months)	9 months	6 months	7 months	7 months
Commercial \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	10 months	11 months	9 months	16 months
Weighted Average Interest Rate Reduction	0.71%	0.52%	1.36%	0.56%
Weighted Average Payment Delay (in Months)	10 months	23 months	10 months	11 months
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	21 months	24 months	23 months	16 months
Weighted Average Interest Rate Reduction	2.44%	3.01%	2.45%	2.39%
Weighted Average Payment Delay (in Months)	3 months	8 months	3 months	6 months
Consumer \| Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	19 months	21 months	18 months	14 months
Weighted Average Interest Rate Reduction	2.36%	1.52%	2.23%	1.21%
Weighted Average Payment Delay (in Months)	3 months	8 months	3 months	6 months
Consumer \| Revolving mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	34 months	58 months	47 months	48 months
Weighted Average Interest Rate Reduction	2.34%	4.36%	2.68%	4.04%
Weighted Average Payment Delay (in Months)	0 months	0 months	0 months	5 months
Consumer \| Auto
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	22 months	18 months	24 months	19 months
Weighted Average Interest Rate Reduction	0.00%	0.00%	0.47%	0.00%
Weighted Average Payment Delay (in Months)	0 months	0 months	0 months	0 months
Consumer \| Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	0 months	60 months	0 months	60 months
Weighted Average Interest Rate Reduction	7.43%	11.41%	8.70%	9.93%
Weighted Average Payment Delay (in Months)	0 months	0 months	0 months	0 months

Financing Receivable, Excluding Accrued Interest, Modified, Amortized Cost of loans

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- Definition

Financing Receivable, Modified, Weighted Average Payment Delay

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-3

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(c)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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- Definition

Percentage of decrease in weighted-average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

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- Definition

Period of increase in weighted-average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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