Retirement Plans (Details Textuals) (Details) - Pension Plan [Member] - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
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 benefit allocations 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. As part of acquisition-related integration activities, employees who become eligible for participation in the RAP are generally provided service credit for their employment with the acquired institution for eligibility and vesting purposes.
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 0	$ 0