v3.26.1
Accumulated Other Comprehensive Income (Loss) - Accumulated Other Comprehensive Income (Loss) Balances, Net of Tax (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Mar. 31, 2026
Jun. 30, 2025
Mar. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
Net Unrealized Holding Gain (Loss) on Securities Available for Sale, Net of Tax [Member]            
Accumulated Other Comprehensive Income (Loss) [Abstract]            
Balance $ (13,321) $ (12,055) $ (17,765) $ (21,713) $ (12,055) $ (21,713)
Other comprehensive income (loss) - before reclassifications (734)   2,336   (2,000) 6,284
Amount reclassified from accumulated other comprehensive income 0   0   0 0
Other comprehensive income (loss), net of tax (734)   2,336   (2,000) 6,284
Balance (14,055) (13,321) (15,429) (17,765) (14,055) (15,429)
Net Change in Overfunded Position in Pension and Postretirement Plans Arising During the Year, Net of Tax [Member]            
Accumulated Other Comprehensive Income (Loss) [Abstract]            
Balance 26,962 26,962 21,266 21,266 26,962 21,266
Other comprehensive income (loss) - before reclassifications 0   0   0 0
Amount reclassified from accumulated other comprehensive income 0   0   0 0
Other comprehensive income (loss), net of tax 0   0   0 0
Balance 26,962 26,962 21,266 21,266 26,962 21,266
Net Change in Net Actuarial Gain and Prior Service Cost on Pension and Postretirement Benefit Plans, Net of Tax [Member]            
Accumulated Other Comprehensive Income (Loss) [Abstract]            
Balance (5,400) (4,883) (3,633) (3,414) (4,883) (3,414)
Other comprehensive income (loss) - before reclassifications 0   0   0 0
Amount reclassified from accumulated other comprehensive income (540)   (541)   (1,057) (760)
Other comprehensive income (loss), net of tax (540)   (541)   (1,057) (760)
Balance (5,940) (5,400) (4,174) (3,633) (5,940) (4,174)
Accumulated Other Comprehensive Income (Loss) [Member]            
Accumulated Other Comprehensive Income (Loss) [Abstract]            
Balance 8,241 10,024 (132) (3,861) 10,024 (3,861)
Other comprehensive income (loss) - before reclassifications (734)   2,336   (2,000) 6,284
Amount reclassified from accumulated other comprehensive income (540)   (541)   (1,057) (760)
Other comprehensive income (loss), net of tax (1,274) (1,783) 1,795 3,729 (3,057) 5,524
Balance $ 6,967 $ 8,241 $ 1,663 $ (132) $ 6,967 $ 1,663