ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Accumulated Other Comprehensive income (loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accumulated other comprehensive income (loss), net of tax:
Balance	$ 1,226,225	$ 1,169,583	$ 1,192,620
Net other comprehensive income (loss) during the period	46,561	2,800	(88,198)
Balance	1,396,517	1,226,225	1,169,583
AOCI Attributable to Parent [Member]
Accumulated other comprehensive income (loss), net of tax:
Balance	(91,579)	(94,379)	(6,181)
Other comprehensive income (loss) before reclassifications	7,834	(702)
Amounts reclassified from accumulated other comprehensive income (loss)	38,727	3,502
Net other comprehensive income (loss) during the period	46,561	2,800	(88,198)
Balance	(45,018)	(91,579)	(94,379)
Securities
Accumulated other comprehensive income (loss), net of tax:
Balance	(90,242)	(100,870)
Other comprehensive income (loss) before reclassifications	14,703	7,498
Amounts reclassified from accumulated other comprehensive income (loss)	31,772	3,130
Net other comprehensive income (loss) during the period	46,475	10,628
Balance	(43,767)	(90,242)	(100,870)
Defined Benefit Plans
Accumulated other comprehensive income (loss), net of tax:
Balance	(6,430)	(5,266)
Other comprehensive income (loss) before reclassifications	(1,087)	(109)
Amounts reclassified from accumulated other comprehensive income (loss)	18	(1,055)
Net other comprehensive income (loss) during the period	(1,069)	(1,164)
Balance	(7,499)	(6,430)	(5,266)
Derivatives
Accumulated other comprehensive income (loss), net of tax:
Balance	5,093	11,757
Other comprehensive income (loss) before reclassifications	(5,782)	(8,091)
Amounts reclassified from accumulated other comprehensive income (loss)	6,937	1,427
Net other comprehensive income (loss) during the period	1,155	(6,664)
Balance	$ 6,248	$ 5,093	$ 11,757