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COMMITMENTS, CONTINGENT LIABILITIES AND RESTRICTIONS (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2025	Dec. 31, 2024	Jun. 30, 2025	Sep. 30, 2024
Commitments and contingencies
Contract amount of commitments and contingencies	$ 1,873,033	$ 1,873,033	$ 1,715,754
Solar energy tax credits investments
Commitments and contingencies
Investment in tax credits				$ 8,500	$ 10,000
Unfunded commitments	3,400	3,400	1,300
Commitments Fund	3,300	6,400
Federal tax credits	2,500	5,000
Amortization of income tax credit investments	2,700	5,500
Income tax credit investments balance	4,200		1,400
Commitments to extend credit
Commitments and contingencies
Contract amount of commitments and contingencies	1,789,624	1,789,624	1,635,509
Standby letters of credit
Commitments and contingencies
Contract amount of commitments and contingencies	$ 83,409	$ 83,409	$ 80,245

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Amount of investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under program not meeting condition for accounting under proportional amortization method.

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