Note 4 - Loans Held for Investment, Net - Impaired Loans (Details) - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Impaired loans, with no related allowance recorded, recorded investment	$ 3,590,539	$ 3,643,608
Impaired loans, with no related allowance recorded, principal net of charge-offs,	3,590,539	3,643,608
Impaired loans, with no related allowance recorded, average recorded investment	3,600,833	3,663,931
Impaired loans, with an 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	3,590,539	3,643,608
Impaired loans, principal net of charge-offs	3,590,539	3,643,608
Impaired loans, average recorded investment	3,600,833	3,663,931
Commercial Real Estate Portfolio Segment [Member]
Impaired loans, with no related allowance recorded, recorded investment	2,982,136	2,993,923
Impaired loans, with no related allowance recorded, principal net of charge-offs,	2,982,136	2,993,923
Impaired loans, with no related allowance recorded, average recorded investment	2,989,009	3,007,495
Impaired loans, related allowance	0	0
Impaired loans, fair value disclosure	2,982,136	2,993,923
Impaired loans, principal net of charge-offs	2,982,136	2,993,923
Impaired loans, average recorded investment	2,989,009	3,007,495
One-to-four Family Residential Real Estate Portfolio Segment [Member]
Impaired loans, with no related allowance recorded, recorded investment	608,403	649,685
Impaired loans, with no related allowance recorded, principal net of charge-offs,	608,403	649,685
Impaired loans, with no related allowance recorded, average recorded investment	611,824	656,436
Impaired loans, related allowance	0	0
Impaired loans, fair value disclosure	608,403	649,685
Impaired loans, principal net of charge-offs	608,403	649,685
Impaired loans, average recorded investment	611,824	656,436
Commercial and Industrial Portfolio Segment [Member]
Impaired loans, with no related allowance recorded, recorded investment
Impaired loans, with no related allowance recorded, principal net of charge-offs,
Impaired loans, with no related allowance recorded, average recorded investment
Impaired loans, related allowance	0	0
Impaired loans, fair value disclosure
Impaired loans, principal net of charge-offs
Impaired loans, average recorded investment
Consumer and Other Portfolio Segment [Member]
Impaired loans, with no related allowance recorded, recorded investment	0	0
Impaired loans, with no related allowance recorded, principal net of charge-offs,	0	0
Impaired loans, with no related allowance recorded, average recorded investment	0	0
Impaired loans, related allowance	0	0
Impaired loans, fair value disclosure	0	0
Impaired loans, principal net of charge-offs	0	0
Impaired loans, average recorded investment	$ 0	$ 0

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
-Section 50
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-Subparagraph (c)(1)
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