FAIR VALUE MEASUREMENTS - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Fair Value Measurements Disclosure [Line Items]
Percentage of securities using market-based information	100.00%
Collateral dependent loans, allowance for credit loss	$ 30.4
Provision for fair value measurements included in allowance for loan losses	$ 58.4
Short-term borrowings approximate fair value for amounts that mature, days, less than	90 days
Fair value, measurements, recurring
Fair Value Measurements Disclosure [Line Items]
Transfer into (from) level 3	$ 84.6
Fair value, measurements, nonrecurring
Fair Value Measurements Disclosure [Line Items]
Collateral dependent loans carrying value	125.5
Carrying amount of OREO	0.9
Valuation allowance of OREO	0.6
Valuation allowance loss in earnings	0.7
Mortgage Servicing Rights \| Fair value, measurements, nonrecurring
Fair Value Measurements Disclosure [Line Items]
Loan servicing rights	1.9
Valuation allowance for impairment of recognized servicing assets	0.1
SBA-Guaranteed Loan Servicing \| Fair value, measurements, nonrecurring
Fair Value Measurements Disclosure [Line Items]
Loan servicing rights	1.7
Valuation allowance for impairment of recognized servicing assets	0.4	$ 0.6
Valuation allowance for impairment of recognized servicing assets, recoveries	0.2
Minimum \| Commercial Loan
Fair Value Measurements Disclosure [Line Items]
Financing receivable, individual reserves in default, threshold	1.0
Maximum \| Commercial and Consumer Loans
Fair Value Measurements Disclosure [Line Items]
Financing receivable, individual reserves in default, threshold	$ 1.0

Collateral Dependent Loans, Allowance for Credit Loss

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Collateral Dependent Loans Carrying Value

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Fair Value Measurements Disclosure [Line Items]

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Financing Receivable, Individual Reserves In Default, Threshold

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Amount of gain (loss) included in earnings relating to other real estate owned that is measured at fair value on a non-recurring basis.

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Carrying amount of other real estate owned that is measured at fair value on a non-recurring basis.

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Percentage of available for sale securities for which market-based or market-derived information, level 1 or level 2 measurements, are used to measure fair value.

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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.

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Maximum number of days to maturity for which the carrying amount for short-term borrowings approximates the fair value for these borrowings.

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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 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-3

Reference 2: 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

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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
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-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
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-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 (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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Amount of 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 recoveries recognized.

+ 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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