LOANS AND LEASES - Schedule of Financial Effects of Loans Modified (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	10 months	11 months
Weighted Average Interest Rate Reduction	1.27%	2.06%
Weighted Average Payment Delay (in Months)	9 months	7 months
Loan modifications	$ 1	$ 1
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	10 months	10 months
Weighted Average Interest Rate Reduction	1.25%	1.65%
Weighted Average Payment Delay (in Months)	9 months	7 months
Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	9 months	17 months
Weighted Average Interest Rate Reduction	1.76%	1.65%
Weighted Average Payment Delay (in Months)	9 months	10 months
Commercial \| Owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	8 months	8 months
Weighted Average Interest Rate Reduction	1.75%	0.00%
Weighted Average Payment Delay (in Months)	10 months	6 months
Commercial \| Investor dependent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	12 months	12 months
Weighted Average Interest Rate Reduction	0.00%	0.00%
Weighted Average Payment Delay (in Months)	7 months	5 months
Commercial \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	17 months	6 months
Weighted Average Interest Rate Reduction	0.05%	0.00%
Weighted Average Payment Delay (in Months)	9 months	6 months
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	14 months	24 months
Weighted Average Interest Rate Reduction	2.20%	2.41%
Weighted Average Payment Delay (in Months)	4 months	5 months
Consumer \| Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	11 months	22 months
Weighted Average Interest Rate Reduction	1.63%	1.87%
Weighted Average Payment Delay (in Months)	4 months	5 months
Consumer \| Revolving mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	39 months	60 months
Weighted Average Interest Rate Reduction	3.49%	3.21%
Weighted Average Payment Delay (in Months)	0 months	5 months
Consumer \| Auto
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	24 months	20 months
Weighted Average Interest Rate Reduction	0.24%	0.00%
Weighted Average Payment Delay (in Months)	0 months	4 months
Consumer \| Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Term Extension (in Months)	0 months	0 months
Weighted Average Interest Rate Reduction	11.80%	9.97%
Weighted Average Payment Delay (in Months)	0 months	0 months

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

No definition available.

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- Definition

Financing Receivable, Modified, Weighted Average Payment Delay

+ References

No definition available.

+ Details

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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 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: 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 the reported fact of one year, five months, and thirteen days.

+ References

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