Note 4 - Loans Held for Investment, Net - Nonperforming Receivables Past Due (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Past due loans	$ 2,948,934	$ 2,828,957
Current loans	259,073,574	242,029,142
Total gross loans	262,022,508	244,858,099
Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	481,715	1,797,714
Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	116,977	501,316
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans	2,350,242	529,927
Commercial Real Estate Portfolio Segment [Member]
Past due loans	796,154	550,000
Current loans	214,075,634	195,264,205
Total gross loans	214,871,788	195,814,205
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	246,154	550,000
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	0	0
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans	550,000	0
One-to-four Family Residential Real Estate Portfolio Segment [Member]
Past due loans	878,070	678,302
Current loans	28,235,990	29,298,323
Total gross loans	29,114,060	29,976,625
One-to-four Family Residential Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	235,561	108,080
One-to-four Family Residential Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	116,977	501,316
One-to-four Family Residential Real Estate Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans	525,532	68,906
Commercial and Industrial Portfolio Segment [Member]
Past due loans	1,274,710	1,600,655
Current loans	11,021,598	8,275,365
Total gross loans	12,296,308	9,876,020
Commercial and Industrial Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	0	1,139,634
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	1,274,710	461,021
Consumer and Other Portfolio Segment [Member]
Past due loans	0	0
Current loans	5,740,352	9,191,249
Total gross loans	5,740,352	9,191,249
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://www.xbrl.org/2003/role/presentationRef
-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.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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