v3.26.1
EMPLOYEE BENEFIT PLANS - Net Periodic Pension Cost (Details) - Pension plan - USD ($)
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Net periodic pension cost included in the Bank's consolidated statements of income    
Service cost $ 283,000 $ 301,000
Interest cost $ 533,000 $ 570,000
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] Labor and Related Expense Labor and Related Expense
Expected return on plan assets $ (934,000) $ (854,000)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Labor and Related Expense Labor and Related Expense
Amortization of net actuarial gain $ (281,000) $ (118,000)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Labor and Related Expense Labor and Related Expense
Net periodic pension (income) cost $ (399,000) $ (101,000)
Other disclosures    
Employer contributions $ 0 $ 0