Note 3 - Loans Held for Investment, Net - Nonperforming Receivables Past Due (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Past due loans	$ 2,144,527	$ 2,948,934
Current loans	282,413,237	259,073,574
Total, gross loans	284,557,764	262,022,508
Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	7,000	481,715
Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	50,314	116,977
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans	2,087,213	2,350,242
Commercial Real Estate Portfolio Segment [Member]
Past due loans	550,000	796,154
Current loans	230,753,130	214,075,634
Total, gross loans	231,303,130	214,871,788
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans		246,154
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans		0
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans	550,000	550,000
One-to-four Family Residential Real Estate Portfolio Segment [Member]
Past due loans	484,838	878,070
Current loans	29,653,420	28,235,990
Total, gross loans	30,138,258	29,114,060
One-to-four Family Residential Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	7,000	235,561
One-to-four Family Residential Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	50,314	116,977
One-to-four Family Residential Real Estate Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans	427,524	525,532
Commercial and Industrial Portfolio Segment [Member]
Past due loans	1,109,689	1,274,710
Current loans	15,451,303	11,021,598
Total, gross loans	16,560,992	12,296,308
Commercial and Industrial Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	0	0
Commercial and Industrial Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	0	0
Commercial and Industrial Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans	1,109,689	1,274,710
Consumer and Other Portfolio Segment [Member]
Past due loans	0	0
Current loans	6,555,384	5,740,352
Total, gross loans	6,555,384	5,740,352
Consumer and Other Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	0	0
Consumer and Other Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	0	0
Consumer and Other Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans	$ 0	$ 0

Financing receivables that are current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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