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Retirement Plans (Details Textual) - USD ($) $ in Thousands | 12 Months Ended
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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% |  |

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- Definition Defined benefit plan actual percentage return on plan assets + References No definition available. + Details
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- Definition Defined Benefit Plan, Health Care Cost Trend, Actual Rate Change + References No definition available. + Details
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (l) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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