Note 4 - Loans and Allowance for Loan Losses - Loans by Credit Quality (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Rating:
Loans receivable	$ 624,592,058	$ 544,398,300
Real Estate, Construction [Member]
Rating:
Loans receivable	62,046,871	40,912,307
Commercial Real Estate Portfolio Segment [Member]
Rating:
Loans receivable	266,292,510	249,580,873
Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Rating:
Loans receivable	107,750,990	106,410,559
Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Rating:
Loans receivable	74,653,469	48,483,523
Commercial Portfolio Segment [Member]
Rating:
Loans receivable	90,186,600	75,404,732
Consumer and Other Loans [Member]
Rating:
Loans receivable	23,661,618	23,606,306
Pass [Member]
Rating:
Loans receivable	599,464,000	518,988,000
Pass [Member] | Real Estate, Construction [Member]
Rating:
Loans receivable	56,737,000	35,465,000
Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Rating:
Loans receivable	259,020,000	242,200,000
Pass [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Rating:
Loans receivable	97,921,000	100,367,000
Pass [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Rating:
Loans receivable	73,870,000	48,483,000
Pass [Member] | Commercial Portfolio Segment [Member]
Rating:
Loans receivable	88,441,000	69,093,000
Pass [Member] | Consumer and Other Loans [Member]
Rating:
Loans receivable	23,475,000	23,380,000
Special Mention [Member]
Rating:
Loans receivable	12,788,000	13,016,000
Special Mention [Member] | Real Estate, Construction [Member]
Rating:
Loans receivable	0	0
Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Rating:
Loans receivable	5,615,000	5,922,000
Special Mention [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Rating:
Loans receivable	6,190,000	2,591,000
Special Mention [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Rating:
Loans receivable	783,000	0
Special Mention [Member] | Commercial Portfolio Segment [Member]
Rating:
Loans receivable	200,000	4,503,000
Special Mention [Member] | Consumer and Other Loans [Member]
Rating:
Loans receivable	0	0
Substandard [Member]
Rating:
Loans receivable	11,656,000	11,810,000
Substandard [Member] | Real Estate, Construction [Member]
Rating:
Loans receivable	5,310,000	5,447,000
Substandard [Member] | Commercial Real Estate Portfolio Segment [Member]
Rating:
Loans receivable	1,657,000	1,459,000
Substandard [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Rating:
Loans receivable	3,640,000	3,453,000
Substandard [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Rating:
Loans receivable	0	0
Substandard [Member] | Commercial Portfolio Segment [Member]
Rating:
Loans receivable	862,000	1,225,000
Substandard [Member] | Consumer and Other Loans [Member]
Rating:
Loans receivable	187,000	226,000
Doubtful [Member]
Rating:
Loans receivable	684,000	584,000
Doubtful [Member] | Real Estate, Construction [Member]
Rating:
Loans receivable	0	0
Doubtful [Member] | Commercial Real Estate Portfolio Segment [Member]
Rating:
Loans receivable		0
Doubtful [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Rating:
Loans receivable	0	0
Doubtful [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Rating:
Loans receivable	0	0
Doubtful [Member] | Commercial Portfolio Segment [Member]
Rating:
Loans receivable	684,000	584,000
Doubtful [Member] | Consumer and Other Loans [Member]
Rating:
Loans receivable	$ 0	$ 0