Note 15 - Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Federal tax at the statutory rate	$ 312,735	$ 791,867
Federal tax at the statutory rate, tax rate	21.00%	34.00%
State income taxes, net of Federal tax benefit	$ 58,156	$ 73,896
State income taxes, net of Federal tax benefit, tax rate	4.00%	3.00%
Bank-owned life insurance	$ (59,303)	$ (74,019)
Bank-owned life insurance, tax rate	(4.00%)	(3.00%)
Meals & entertainment	$ 9,169
Meals & entertainment, tax rate	1.00%
Net deferred tax asset revaluation adjustment		$ 1,150,318
Net deferred tax asset revaluation adjustment, tax rate		49.00%
Other, net	$ 94,942	$ 26,366
Other, net, tax rate	6.00%	1.00%
Provision (benefit) for income taxes	$ 415,699	$ 1,968,428
Provision (benefit) for income taxes, tax rate	28.00%	85.00%

Amount of deferred income tax expense (benefit) pertaining to revaluation adjustments.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to bank-owned life insurance.

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