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Retirement Plans (Details Textual) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2031
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
RAP        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Description   The Corporation has a noncontributory defined benefit RAP, covering substantially all employees who meet participation requirements. The benefits are based primarily on years of service and the employee’s compensation paid. Employees of acquired entities generally participate in the RAP after consummation of the business combinations. Any retirement plans of acquired entities are typically merged into the RAP after completion of the mergers, and credit is usually given to employees for years of service at the acquired institution for vesting and eligibility purposes.    
Defined Benefit Plan Actual Return on Plan Assets Percentage   10.16% 15.80%  
Defined Benefit Plan, Plan Assets, Contributions by Employer   $ 0 $ 0  
Other Postretirement Benefits Plan [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Description   The Corporation also provides legacy healthcare access to a limited group of retired employees from a previous acquisition in the Postretirement Plan. There are no other active retiree healthcare plans.    
Defined Benefit Plan, Plan Assets, Contributions by Employer   $ 183 171  
Defined Benefit Plan, Health Care Cost Trend, Actual Rate Change   35.72%    
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year   6.00%    
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate   5.00%    
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate 2031      
401(k) plan        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Contribution Plan, Cost   $ 17,000 $ 16,000 $ 15,000
Minimum [Member] | RAP | Defined Benefit Plan, Equity Securities, US [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage   50.00%    
Minimum [Member] | RAP | Defined Benefit Plan, Debt Security [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage   30.00%    
Minimum [Member] | RAP | Other Cash Equivalents        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage   0.00%    
Minimum [Member] | RAP | Defined Benefit Plan, Alternative Securities [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage   0.00%    
Maximum [Member] | RAP | Defined Benefit Plan, Equity Securities, US [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage   70.00%    
Maximum [Member] | RAP | Defined Benefit Plan, Debt Security [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage   50.00%    
Maximum [Member] | RAP | Other Cash Equivalents        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage   10.00%    
Maximum [Member] | RAP | Defined Benefit Plan, Alternative Securities [Member]        
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]        
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage   15.00%