Note 3 - Investments - Amortized Cost and Fair Value of Debt Securities By Contractual Maturity (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
After one year through five years, amortized cost	$ 1,472,228	$ 612,088
After one year through five years, fair value	1,462,745	617,562
After five years through ten years, amortized cost	2,101,676	1,910,307
After five years through ten years, fair value	2,055,173	1,945,454
More than 10 years, amortized cost	20,430,838	15,740,739
More than 10 years, fair value	19,492,496	16,196,403
Total amortized cost and fair value	27,957,697	22,439,705
Total amortized cost and fair value	26,882,239	22,945,700
Redeemable Preferred Stock [Member]
Debt securities, amortized cost	99,560	99,560
Debt securities, fair value	90,840	100,520
Collateralized Mortgage Backed Securities [Member]
Debt securities, amortized cost	3,853,395	4,077,011
Debt securities, fair value	$ 3,780,985	$ 4,085,761

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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