Note 2 - Investments - Amortized Cost and Fair Value of Debt Securities By Contractual Maturity (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
After one year through five years, amortized cost	$ 809,137	$ 612,088
After one year through five years, fair value	793,989	617,562
After five years through ten years, amortized cost	1,757,227	1,910,307
After five years through ten years, fair value	1,714,964	1,945,454
More than 10 years, amortized cost	17,323,758	15,740,739
More than 10 years, fair value	16,675,852	16,196,403
Total, amortized cost	23,987,179	22,439,705
Total, fair value	23,183,390	22,945,700
Redeemable Preferred Stock [Member]
Debt securities, amortized cost	99,560	99,560
Debt securities, fair value	97,760	100,520
Collateralized Mortgage Backed Securities [Member]
Debt securities, amortized cost	3,997,497	4,077,011
Debt securities, fair value	$ 3,900,825	$ 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
-Paragraph 2
-Subparagraph (a)
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