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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount excluding accrued interest, of increase in financing receivable from purchase. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount at par value of financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount at purchase price of financing receivable purchased with credit deterioration.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of discount (premium) attributable to other factors on financing receivable purchased with credit deterioration.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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LOANS AND ALLOWANCE FOR CREDIT LOSSES - PCD Loans (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended		12 Months Ended
	Jul. 31, 2025	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for credit loss expense			$ 0
Allowance for credit losses		$ 33,940	31,761	$ 33,940	$ 34,052	$ 32,231	$ 28,885	$ 28,744
Unpaid Principal Balance		11,200		11,200
Carrying Value			3,581,871		3,571,807
Municipal and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		128	93	128	119	95	110	128
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		919	827	919	814	778	786	741
Total commercial loans \| Commercial construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		2,522	4,906	2,522	4,371	4,877	2,032	2,096
Total commercial real estate \| Commercial Real Estate Owner Occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		3,191	3,481	3,191	4,045	3,459	2,823	2,794
Total commercial real estate \| Commercial Real Estate Non-Owner Occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		12,699	11,679	12,699	12,837	11,512	10,980	11,104
Total commercial and industrial \| Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		6,285	4,791	6,285	5,378	5,729	5,664	5,064
Total residential real estate \| Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		8,024	5,778	8,024	6,350	5,640	6,406	6,732
Total consumer \| Consumer other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		$ 172	206	$ 172	138	$ 141	$ 84	$ 85
Acquired PSL loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses			333		751
Unpaid Principal Balance			7,840		9,726
Carrying Value			7,431		9,234
Fair value of PCD loans at acquisition	$ 8,887
Non-credit related discount	713
Allowance for credit losses on PCD loans	1,622
Par value of PCD loans at acquisition	$ 11,222
Acquired PSL loans \| Commercial Real Estate Owner Occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance			1,022		1,103
Carrying Value			958		1,032
Acquired PSL loans \| Commercial Real Estate Non-Owner Occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance			4,532		4,632
Carrying Value			4,297		4,359
Acquired PSL loans \| Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance			490		2,139
Carrying Value			466		2,104
Acquired PSL loans \| Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance			1,254		1,306
Carrying Value			1,172		1,221
Acquired PSL loans \| Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance			502		506
Carrying Value			499		479
Acquired PSL loans \| Consumer other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance			40		40
Carrying Value			$ 39		$ 39