Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	$ 1,380,294	$ 1,283,445	$ 1,184,659
Net Change	35,285	13,909	21,224
Balance at end of period	1,463,877	1,380,294	1,283,445
Change in net unrealized gains (losses) on available-for-sale debt securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(56,308)	(64,553)
Net Change	28,932	8,245
Balance at end of period	(27,376)	(56,308)	(64,553)
Change in interest rate swap
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(7,526)	(11,602)
Net Change	5,938	4,076
Balance at end of period	(1,588)	(7,526)	(11,602)
Adjustment to funded status of employee benefit plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(13,158)	(14,746)
Net Change	415	1,588
Balance at end of period	(12,743)	(13,158)	(14,746)
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(76,992)	(90,901)	(112,125)
Net Change	35,285	13,909	21,224
Balance at end of period	$ (41,707)	$ (76,992)	$ (90,901)