CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 64,443	$ 66,555	$ 47,700
Other comprehensive income (loss):
Change in net unrealized holding gains (losses) on available-for-sale securities and I/O strips	6,148	(19,079)	(2,953)
Deferred income taxes	(1,783)	5,532	1,177
Change in net unamortized unrealized gain on securities available-for- sale that were reclassified to securities held-to-maturity			(371)
Deferred income taxes			110
Change in unrealized gains (losses) on securities and I/O strips, net of deferred income taxes	4,365	(13,547)	(2,037)
Change in net pension and other benefit plan liability adjustment	(458)	9,909	2,219
Deferred income taxes	219	(2,222)	(461)
Change in pension and other benefit plan liability, net of deferred income taxes	(239)	7,687	1,758
Other comprehensive income (loss)	4,126	(5,860)	(279)
Total comprehensive income	$ 68,569	$ 60,695	$ 47,421