Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Consolidated Statements of Comprehensive Income (Loss) [Abstract]
Net income	$ 140,641	$ 118,782	$ 151,995
Securities available for sale:
Unrealized net holding gains (losses) arising during the period, gross	19,585	22,987	(209,212)
Tax effect	(4,896)	(5,746)	52,303
Unrealized net holding gains (losses) arising during the period, net	14,689	17,241	(156,909)
Reclassification adjustment for net losses in net income, gross	0	9,450	0
Tax effect	0	(2,363)	0
Reclassification adjustment for net losses in net income, net	0	7,087	0
Amortization of unrealized net gains for the reclassification of available for sale securities to held to maturity, gross	356	427	513
Tax effect	(89)	(107)	(128)
Amortization of unrealized net gains for the reclassification of available for sale securities to held to maturity, net	267	320	385
Total securities available for sale, net	14,956	24,648	(156,524)
Pension and other benefits:
Amortization of prior service cost and actuarial losses, gross	2,881	2,640	737
Tax effect	(720)	(660)	(184)
Amortization of prior service cost and actuarial losses, net	2,161	1,980	553
Decrease (increase) in unrecognized actuarial loss, gross	2,292	3,296	(14,292)
Tax effect	(573)	(824)	3,573
Decrease (increase) in unrecognized actuarial loss, net	1,719	2,472	(10,719)
Total pension and other benefits, net	3,880	4,452	(10,166)
Total other comprehensive income (loss)	18,836	29,100	(166,690)
Comprehensive income (loss)	$ 159,477	$ 147,882	$ (14,695)