Note 3 - Loans Held for Investment, Net - Nonperforming Receivables Past Due (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Past due loans	$ 6,043,780	$ 2,948,934
Current loans	256,458,145	259,073,574
Total, gross loans	262,501,925	262,022,508
Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	3,711,928	481,715
Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	326,041	116,977
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due loans	2,005,811	2,350,242
Commercial Real Estate Portfolio Segment [Member]
Past due loans	3,709,123	796,154
Current loans	208,891,445	214,075,634
Total, gross loans	212,600,568	214,871,788
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Past due loans	2,893,412	246,154
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	265,711	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	1,059,947	878,070
Current loans	28,880,947	28,235,990
Total, gross loans	29,940,894	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	818,516	235,561
One-to-four Family Residential Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Past due loans	60,330	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	181,101	525,532
Commercial and Industrial Portfolio Segment [Member]
Past due loans	1,274,710	1,274,710
Current loans	12,268,835	11,021,598
Total, gross loans	13,543,545	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	1,274,710	1,274,710
Consumer and Other Portfolio Segment [Member]
Past due loans	0	0
Current loans	6,416,918	5,740,352
Total, gross loans	6,416,918	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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