Consolidated Statements of Comprehensive Income (Loss) (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Consolidated Statements of Comprehensive Income (Loss) (unaudited) [Abstract]
Net income	$ 38,097	$ 24,606	$ 104,636	$ 88,336
Securities available for sale:
Unrealized net holding gains (losses) arising during the period, gross	49,019	(24,059)	45,283	(35,117)
Tax effect	(12,255)	6,015	(11,321)	8,780
Unrealized net holding gains (losses) arising during the period, net	36,764	(18,044)	33,962	(26,337)
Reclassification adjustment for net losses in net income, gross	0	0	0	9,450
Tax effect	0	0	0	(2,363)
Reclassification adjustment for net losses in net income, net	0	0	0	7,087
Amortization of unrealized net gains for the reclassification of available for sale securities to held to maturity, gross	87	105	274	328
Tax effect	(21)	(26)	(68)	(82)
Amortization of unrealized net gains for the reclassification of available for sale securities to held to maturity, net	66	79	206	246
Total securities available for sale, net	36,830	(17,965)	34,168	(19,004)
Pension and other benefits:
Amortization of prior service cost and actuarial losses, gross	471	648	2,374	1,946
Tax effect	(118)	(162)	(594)	(487)
Amortization of prior service cost and actuarial losses, net	353	486	1,780	1,459
Increase in unrecognized actuarial loss, gross	0	0	(1,000)	0
Tax effect	0	0	250	0
Increase in unrecognized actuarial loss, net	0	0	(750)	0
Total pension and other benefits, net	353	486	1,030	1,459
Total other comprehensive income (loss)	37,183	(17,479)	35,198	(17,545)
Comprehensive income	$ 75,280	$ 7,127	$ 139,834	$ 70,791