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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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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		6 Months Ended	12 Months Ended
	Jul. 31, 2025	Jun. 30, 2026	Dec. 31, 2025	Dec. 31, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for credit loss expense		$ 0
Allowance for credit losses		32,231	$ 34,052	$ 34,052	$ 34,315	$ 28,885	$ 28,614	$ 28,744
Carrying Value		3,581,949	3,571,807
Municipal and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		95		119	111	110	112	128
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		778		814	777	786	744	741
Total commercial loans \| Commercial construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		4,877		4,371	4,328	2,032	2,065	2,096
Total commercial real estate \| Commercial Real Estate Owner Occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		3,459		4,045	3,627	2,823	2,830	2,794
Total commercial real estate \| Commercial Real Estate Non-Owner Occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		11,512		12,837	13,809	10,980	10,923	11,104
Total commercial and industrial \| Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		5,729		5,378	5,549	5,664	5,414	5,064
Total residential real estate \| Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		5,640		6,350	5,972	6,406	6,447	6,732
Total consumer \| Consumer other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		141		$ 138	$ 142	$ 84	$ 79	$ 85
Acquired PSL loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses		745	751
Unpaid Principal Balance		9,075	9,726
Carrying Value		8,647	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		1,052	1,103
Carrying Value		985	1,032
Acquired PSL loans \| Commercial Real Estate Non-Owner Occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		4,563	4,632
Carrying Value		4,320	4,359
Acquired PSL loans \| Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		1,651	2,139
Carrying Value		1,625	2,104
Acquired PSL loans \| Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		1,265	1,306
Carrying Value		1,181	1,221
Acquired PSL loans \| Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		504	506
Carrying Value		497	479
Acquired PSL loans \| Consumer other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		40	40
Carrying Value		$ 39	$ 39