Income Taxes - Components of deferred tax assets and liabilities (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Components of deferred tax assets and liabilities
Deferred Loan Fees (Costs)	$ (241,000)	$ (259,000)
Allowance for Loan Losses	124,000	137,000
Federal Home Loan Bank Stock	(78,000)	(69,000)
Deferred Retirement Agreements	63,000	377,000
Tax Carryforward of Loss on Sale of Investment Securities	227,000	456,000
Tax Carryforwards of Net Operating Losses	324,000	15,000
All Other Temporary Differences	30,000	54,000
Deferred Tax Liabilities	449,000	711,000
Valuation Allowance for Deferred Tax Asset (Loss on Sale of Investment Securities)	(227,000)	(456,000)
Valuation Allowance for Deferred Tax Asset (Net Operating Losses)	(222,000)
Deferred Tax Asset Net of Valuation Allowance		255,000
Unrealized Losses on Securities Available-for-Sale	5,000	25,000
Net Deferred Tax Asset	5,000	280,000
Amount of bad debts deductions for which no deferred tax liability recognized	3,986,000	3,986,000
Deferred income tax liability	0	0
Unrecorded deferred income tax liability on bad debts reserve	$ 837,000	$ 837,000