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FAIR VALUE - Assets and liabilities measured on a non-recurring basis (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Feb. 01, 2024
Assets and Liabilities Measured on Nonrecurring Basis
Valuation allowance			$ 3,628	$ 470
Impairment recovery			1,200
Acquisition-related contingent consideration adjustment			244	3,280	$ (300)
Payment of contingent consideration			$ 3,087	1,214	$ 0
FBD
Assets and Liabilities Measured on Nonrecurring Basis
Estimated probability of achievement			100.00%
Payment of contingent consideration	$ 2,700
TGA
Assets and Liabilities Measured on Nonrecurring Basis
Acquisition-related contingent consideration adjustment				1,000
Payment of contingent consideration		$ 2,400
Fair value of the remaining contingent consideration liability	$ 800
CPD
Assets and Liabilities Measured on Nonrecurring Basis
Payment of contingent consideration			$ 1,500
Fair value of the remaining contingent consideration liability						$ 3,000
Maximum | FBD
Assets and Liabilities Measured on Nonrecurring Basis
Acquisition-related contingent consideration adjustment				2,700
Maximum | CPD
Assets and Liabilities Measured on Nonrecurring Basis
Acquisition-related contingent consideration adjustment			1,900
Mortgage servicing rights
Assets and Liabilities Measured on Nonrecurring Basis
Valuation allowance			100	1,200
Level 3 | Minimum | Probability of achievement
Assets and Liabilities Measured on Nonrecurring Basis
Contingent consideration, measurement input 2				100,000
Non-recurring
Assets and Liabilities Measured on Nonrecurring Basis
Individually assessed loans			19,315	3,014
Other real estate owned			2,781	1,159
Mortgage servicing rights			460	162
Contingent consideration			(4,140)	(5,150)
Total			18,416	(815)
Non-recurring | Level 1
Assets and Liabilities Measured on Nonrecurring Basis
Individually assessed loans			0	0
Other real estate owned			0	0
Mortgage servicing rights			0	0
Contingent consideration			0	0
Total			0	0
Non-recurring | Level 2
Assets and Liabilities Measured on Nonrecurring Basis
Individually assessed loans			0	0
Other real estate owned			0	0
Mortgage servicing rights			0	0
Contingent consideration			0	0
Total			0	0
Non-recurring | Level 3
Assets and Liabilities Measured on Nonrecurring Basis
Individually assessed loans			19,315	3,014
Other real estate owned			2,781	1,159
Mortgage servicing rights			460	162
Contingent consideration			(4,140)	(5,150)
Total			$ 18,416	$ (815)

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- Definition

Percentage of estimated possibility of achievement with respect to revaluation of contingent consideration arrangements.

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Amount of allowance for credit losses related to specifically allocated.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value of asset after deduction of liability.

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The adjustment to the carrying value of the rights retained or purchased to service mortgages. These adjustments are made when the estimate of the fair value is changed. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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Amount of cash outflow, not made soon after acquisition date of business combination, to settle contingent consideration liability up to amount recognized at acquisition date, including, but not limited to, measurement period adjustment and less amount paid soon after acquisition date.

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Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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