v3.26.1
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Schedule of Other Comprehensive Income (Loss) (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Unrealized gain on available for sale securities reclassified from accumulated other comprehensive income into interest income from fair value hedges $ 203 $ 0 $ 0 $ 0
Other comprehensive (loss) income, before tax (5,745) 5,915 (11,883) 21,406
Income Tax Effect 1,535 (1,589) 3,175 (5,751)
Total other comprehensive (loss) income, net of taxes (4,210) 4,326 (8,708) 15,655
Total Accumulated Other Comprehensive Loss        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Other comprehensive (loss) income, before tax     (11,883) 21,406
Income Tax Effect     3,175 (5,751)
Total other comprehensive (loss) income, net of taxes (4,210) 4,326 (8,708) 15,655
Total unrealized gains (losses) on Benefit Plans        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Other comprehensive (loss) income, before tax 43 40 86 82
Income Tax Effect (12) (11) (25) (22)
Total other comprehensive (loss) income, net of taxes 31 29 61 60
Unrealized gains (losses) on available for sale securities        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Other comprehensive (loss) income, before tax (4,259) 6,016 (9,676) 21,368
Income Tax Effect 1,137 (1,615) 2,585 (5,740)
Total other comprehensive (loss) income, net of taxes (3,122) 4,401 (7,091) 15,628
Unrealized holding (losses) gains on available for sale securities        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Other comprehensive income (loss), before reclassifications, before tax (4,751) 4,493 (11,429) 18,663
Reclassification adjustment for net losses realized in income        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Reclassification adjustment 39 1,041 861 1,721
Accretion of net unrealized loss on securities transferred to held-to-maturity        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Reclassification adjustment 453 482 892 984
Other comprehensive (loss) income, before tax     892 984
Income Tax Effect     (239) (264)
Unrealized gains (losses) on derivatives        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Other comprehensive income (loss), before reclassifications, before tax (2,019) (35) (2,623) 177
Other comprehensive (loss) income, before tax (1,529) (141) (2,293) (44)
Income Tax Effect 410 37 615 11
Total other comprehensive (loss) income, net of taxes (1,119) (104) (1,678) (33)
Reclassification adjustment for losses (gains) realized in income from cash flow and fair value hedges        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Reclassification adjustment 287 (106) 330 (221)
Reclassification adjustment for unrealized holding gains on available for sale securities realized in income related to fair value hedges        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Unrealized gain on available for sale securities reclassified from accumulated other comprehensive income into interest income from fair value hedges 203 0 0 0
Postretirement Benefit Plans | Change in obligation for postretirement benefits and for prior service credit        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Other comprehensive income (loss), before reclassifications, before tax 35 33 69 68
Postretirement Benefit Plans | Reclassification adjustment for prior service expense included in other expense and in compensation and employee benefits        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Reclassification adjustment 7 7 14 14
Other Postretirement Benefits Plan | Total unrealized gains (losses) on Benefit Plans        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Other comprehensive (loss) income, before tax $ 1 $ 0 $ 3 $ 0