Note 1 - Basis of Presentation and Accounting Policies (Details Textual)	3 Months Ended								12 Months Ended
	Dec. 31, 2016 USD ($) shares	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) shares	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($)		Dec. 31, 2013 USD ($)
Retained Earnings (Accumulated Deficit)	$ 49,560,595				$ 43,691,073				$ 49,560,595	$ 43,691,073
Income Tax Expense (Benefit)	$ 775,000	$ 948,000	$ 664,000	$ 574,000	$ 484,000	$ 610,000	$ 486,000	$ 257,000	$ 2,961,139	$ 1,837,329	$ 1,349,009	[1]
FHLB ClassB Capital Stock Par Value | $ / shares									$ 100
FHLB Capital Stock to Assets	0.09%								0.09%
Maximum Investment in FHLB Capital Stock	$ 15,000,000								$ 15,000,000
FHLB Outstanding Advances	4.25%								4.25%
FHLB Stock | shares	15,737				23,693				15,737	23,693
Number of Operating Segments									1
Mortgage Servicing Rights (MSR) Impairment (Recovery)									$ 0	$ 0	0
Goodwill, Impairment Loss									0	0	0
Increase in Unrecognized Tax Benefits is Reasonably Possible	$ 0								0
Income Tax Examination, Penalties and Interest Expense									0	$ 0	0
Compensated Absences Liability	$ 0								$ 0
Interest Rate Swap [Member]
Derivative, Amount of Hedged Item											$ 10,000,000
Derivative, Term of Contract											5 years
Core Deposits [Member]
Finite-Lived Intangible Asset, Useful Life									10 years
Leasehold Improvements and Buildings [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life									10 years
Leasehold Improvements and Buildings [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life									40 years
Furniture and Fixtures [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life									3 years
Furniture and Fixtures [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life									7 years
Restatement Adjustment [Member]
Income Tax Expense (Benefit)											$ 217,000
Income Tax Expense Correction [Member] | Restatement Adjustment [Member]
Retained Earnings (Accumulated Deficit)											$ 434,000		$ 651,000

[1] revised for prior period restatement