CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 93,767	$ 103,817	$ 95,733
Change in available-for-sale and transferred securities:
Unrealized holding gain (loss) on securities available-for-sale arising during the period	40,639	(261,256)	(14,553)
Reclassification adjustment for amortization of unrealized losses on securities transferred to held-to-maturity	1,987	1,518	0
Reclassification adjustment for (gains) losses included in net income	25	(21)	(797)
Net securities gain (loss) activity during the period	42,651	(259,759)	(15,350)
Tax effect	(8,957)	54,549	3,224
Net of tax amount	33,694	(205,210)	(12,126)
Defined benefit pension plans:
Net gain (loss) on defined benefit pension plans	(13)	115	390
Amortization of net actuarial loss	59	144	242
Net gain on activity during the period	46	259	632
Tax effect	(12)	(65)	(157)
Net of tax amount	34	194	475
Total other comprehensive income (loss), net of tax	33,728	(205,016)	(11,651)
Comprehensive income (loss)	$ 127,495	$ (101,199)	$ 84,082