Note 8 - Loans and Allowance for Credit Losses - Loans Individually Evaluated for Impairment (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Residential Portfolio Segment [Member] \| One- to Four-family Loan [Member]
Unpaid Contractual Principal Balance	$ 2,303,698	$ 3,014,703
Recorded Investment With No Allowance	1,022,446	1,902,819
Recorded Investment With Allowance	1,197,240	984,641
Total Recorded Investment	2,219,686	2,887,460
Related Allowance	246,778	311,598
Average Recorded Investment	2,715,325	3,596,800
Residential Portfolio Segment [Member] \| Multi-family Loans [Member]
Unpaid Contractual Principal Balance	0	0
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	0	0
Total Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Nonresidential Real Estate Portfolio Segment [Member]
Unpaid Contractual Principal Balance	1,880,189	2,069,922
Recorded Investment With No Allowance	0	389,961
Recorded Investment With Allowance	1,880,189	1,679,961
Total Recorded Investment	1,880,189	2,069,922
Related Allowance	252,352	75,086
Average Recorded Investment	1,956,910	2,114,684
Commercial Portfolio Segment [Member]
Unpaid Contractual Principal Balance	0	0
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	0	0
Total Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	21,789
Consumer Portfolio Segment [Member]
Unpaid Contractual Principal Balance	0	0
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	0	0
Total Recorded Investment	0	0
Related Allowance	0	0
Average Recorded Investment	0	3,464
Purchased Auto Loans [Member]
Unpaid Contractual Principal Balance	12,569	3,069
Recorded Investment With No Allowance	0	3,069
Recorded Investment With Allowance	12,569	0
Total Recorded Investment	12,569	3,069
Related Allowance	6,285	0
Average Recorded Investment	6,826	6,574
Unpaid Contractual Principal Balance	4,196,456	5,087,694
Recorded Investment With No Allowance	1,022,446	2,295,849
Recorded Investment With Allowance	3,089,998	2,664,602
Total Recorded Investment	4,112,444	4,960,451
Related Allowance	505,415	386,684
Average Recorded Investment	$ 4,679,061	$ 5,743,311

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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+ References

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