Note 4 - Loans Held for Investment, Net - Impaired Loans (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Impaired loans, with no related allowance recorded, recorded investment	$ 3,562,937	$ 3,643,608
Impaired loans, with no related allowance recorded, principal net of charge-offs,	3,562,937	3,643,608
Impaired loans, with no related allowance recorded, average recorded investment	3,574,927	3,663,931
Impaired loans, with related allowance recorded, recorded investment	0	0
Impaired loans, with an allowance recorded, principal net of charge-offs	0	0
Impaired loans, related allowance	0	0
Impaired loans, with an allowance recorded, average recorded investment	0	0
Impaired loans, fair value disclosure	3,562,937	3,643,608
Impaired loans, principal net of charge-offs	3,562,937	3,643,608
Impaired loans, average recorded investment	3,574,927	3,663,931
Commercial Real Estate Portfolio Segment [Member]
Impaired loans, with no related allowance recorded, recorded investment	2,976,737	2,993,923
Impaired loans, with no related allowance recorded, principal net of charge-offs,	2,976,737	2,993,923
Impaired loans, with no related allowance recorded, average recorded investment	2,981,161	3,007,495
Impaired loans, related allowance	0	0
Impaired loans, fair value disclosure	2,976,737	2,993,923
Impaired loans, principal net of charge-offs	2,976,737	2,993,923
Impaired loans, average recorded investment	2,981,161	3,007,495
One-to-four Family Residential Real Estate Portfolio Segment [Member]
Impaired loans, with no related allowance recorded, recorded investment	586,200	649,685
Impaired loans, with no related allowance recorded, principal net of charge-offs,	586,200	649,685
Impaired loans, with no related allowance recorded, average recorded investment	593,766	656,436
Impaired loans, related allowance	0	0
Impaired loans, fair value disclosure	586,200	649,685
Impaired loans, principal net of charge-offs	586,200	649,685
Impaired loans, average recorded investment	$ 593,766	$ 656,436

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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-Subparagraph (c)(1)
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