Note 6 - Employee Benefit Plans (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Employee Stock Ownership Plan (ESOP), Debt Structure, Direct Loan, Amount	$ 2,000,000
Employee Stock Ownership Plan Debt Structure Additional Direct Loan Amount	$ 1,942,000
Employee Stock Ownership Plan (ESOP), Shares Subject To Repurchase Obligation (in shares)	0
Employee Stock Ownership Plan (ESOP), Number of Allocated Shares (in shares)	291,980	321,141
Employee Stock Ownership Plan (ESOP), Number of Suspense Shares (in shares)	15,786	26,752
Employee Stock Ownership Plan (ESOP), Compensation Expense	$ 56,000	$ 101,000
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax	(97,000)	(87,000)
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Benefit Obligation	4,097,000	$ 4,262,000	$ 4,062,000
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax	$ 84,000
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year	10.00%
Defined Benefit Plan Decrease In Health Care Cost Trend Rate Each Year	0.50%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	5.00%