Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net income	$ 48,020	$ 46,662	$ 51,168
Other comprehensive income, before tax
Net unrealized gains (losses) on securities	5,669	(19,793)	(1,381)
Reclassification adjustment for net loss recognized in net income	21	0	0
Net unrealized gains on available-for-sale debt securities	5,690	(19,793)	(1,381)
Employee benefit plans:
Net actuarial gain	306	1,718	1,472
Reclassification adjustment for amortization of prior service cost and net actuarial loss recognized in net income	38	135	386
Net unrealized gains on employee benefit plans	344	1,853	1,858
Other comprehensive income (loss), before tax	6,034	(17,940)	477
Income tax (expense) benefit	(1,266)	3,767	(100)
Other comprehensive (loss) income, net	4,768	(14,173)	377
Total comprehensive income	$ 52,788	$ 32,489	$ 51,545