Note O - Employee and Director Benefit Plans (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	75.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	6.00%
Defined Contribution Plan, Employer Contributions	$ 260,000	$ 260,000	$ 260,000
Employee Stock Ownership Plan (ESOP), Number of Allocated Shares (in shares)	214,961	222,891	223,976
Cash Surrender Value of Life Insurance	$ 20,768,000	$ 20,150,000
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	5.20%	2.80%
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax	$ 107,973
Postretirement Life Insurance [Member]
Cash Surrender Value of Life Insurance	$ 329,684	$ 324,538
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	3.00%	3.50%
Directors' Deferred Income Plan [Member]
Defined Benefit Plan, Accumulated Benefit Obligation	$ 111,217	$ 105,076
Certain Key Executives [Member] | Other Postretirement Benefits Plan [Member]
Cash Surrender Value of Life Insurance	$ 2,288,322	$ 2,109,593
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	3.00%	3.50%
Defined Benefit Plan, Accumulated Benefit Obligation	$ 1,646,068	$ 1,559,728
Director [Member] | Other Postretirement Benefits Plan [Member]
Cash Surrender Value of Life Insurance	$ 180,559	$ 172,034
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	3.00%	3.50%
Defined Benefit Plan, Accumulated Benefit Obligation	$ 219,540	$ 208,590
Executive Supplemental Income Plan [Member]
Defined Benefit Plan, Payment Period (Year)		15 years
Executive Supplemental Income Plan [Member] | President and CEO [Member]
Defined Benefit Plan, Percentage of Compensation		67.00%
Executive Supplemental Income Plan [Member] | Executive Vice President [Member]
Defined Benefit Plan, Percentage of Compensation		58.00%
Executive Supplemental Income Plan [Member] | Executive Officer [Member]
Defined Benefit Plan, Percentage of Compensation		50.00%
Directors' Deferred Income Plan [Member]
Defined Benefit Plan, Payment Period (Year)		10 years
Interest on Deferred Fees, Percent		10.00%
Interest on Deferred Fees, Monthly Compounded Interest Rate		7.50%
Cash Surrender Value of Life Insurance	$ 17,969,670	$ 17,544,449
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	3.00%	3.50%
Defined Benefit Plan, Accumulated Benefit Obligation	$ 14,099,626	$ 13,556,638