FAIR VALUE MEASUREMENTS - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025
Fair Value Measurements Disclosure [Line Items]
Collateral dependent loans, allowance for credit loss	$ 21.3
Provision for fair value measurements included in allowance for loan losses	18.3
Fair Value, Nonrecurring
Fair Value Measurements Disclosure [Line Items]
Collateral dependent loans carrying value	75.4
Fair Value, Nonrecurring \| Mortgage Servicing Rights
Fair Value Measurements Disclosure [Line Items]
Carrying value	3.7
MSRs valuation allowance	0.4
Provision for expense	0.3
Loans Receivable \| Fair Value, Recurring
Fair Value Measurements Disclosure [Line Items]
Transfer into (from) level 3	$ 16.8	$ 24.6

Collateral Dependent Loans, Allowance for Credit Loss

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Collateral Dependent Loans Carrying Value

+ References

No definition available.

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Fair Value Measurements Disclosure [Line Items]

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No definition available.

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Amount of provision for loan losses applicable to the current period fair value measurements for impaired loans measured at fair value on a non-recurring basis.

+ References

No definition available.

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- Definition

Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-3

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- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481260/860-50-45-2

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Amount of increase in the valuation allowance for impairment of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer from charges to expense.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (e)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

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Amount of increase (decrease) in the valuation allowance for impairment of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer from expenses (recoveries) recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (e)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

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