Note 9 - Fair Value Measurements - Schedule of Fair Value Reported on a Recurring Basis (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Equity Securities	$ 545,075	$ 454,058
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Equity Securities	545,075	454,058
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Treasury Securities [Member]
Available-for-Sale Securities
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Domestic Equities [Member]
Equity Securities	364,171	259,843
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | International Equities [Member]
Equity Securities	110,629	179,083
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other [Member]
Equity Securities	70,275	15,132
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Equity Securities	18,517,910	16,249,414
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Treasury Securities [Member]
Available-for-Sale Securities	18,517,910	16,249,414
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Domestic Equities [Member]
Equity Securities
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | International Equities [Member]
Equity Securities
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other [Member]
Equity Securities
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Equity Securities
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US Treasury Securities [Member]
Available-for-Sale Securities
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Domestic Equities [Member]
Equity Securities
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | International Equities [Member]
Equity Securities
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other [Member]
Equity Securities