Note 10 - Income Taxes - Difference Between Financial Statement Tax Expense and Amount Computer by Applying Statutory Federal Tax Rate to Income Before Income Taxes (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statutory Federal Income Taxes	$ 3,132,711	$ 4,954,199	$ 4,283,394
Tax-Exempt Interest	(57,271)	(102,345)	(109,759)
Income from Cash Value Life Insurance, net of premiums	(96,733)	(198,730)	(182,532)
Meal and Entertainment Disallowance	9,578	14,354	16,813
Other	11,985	69,029	(156,583)
Tax Expense from Tax Rate Changes		2,040,946
Federal Income Tax Expense	$ 3,000,270	$ 6,777,453	$ 3,851,333

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Amount of current and deferred federal income tax expense (benefit) attributable to income (loss) from continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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