Note 1 - Summary of Significant Accounting Policies - Earnings Per Share (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Net income available to common stockholders	$ 1,261,098	$ 770,962
Basic potential common shares:
Weighted average shares outstanding (in shares)	3,019,749	2,894,123
Weighted average unallocated ESOP shares (in shares)	(59,149)	(23,081)
Weighted average unvested MRP shares (in shares)	(938)	(2,572)
Basic weighted average shares outstanding (in shares)	2,959,662	2,868,470
Dilutive potential common shares:
Dilutive weighted average shares outstanding (in shares)	2,975,713	2,881,242
Basic earnings per share (in dollars per share)	$ 0.43	$ 0.27
Diluted earnings per share (in dollars per share)	$ 0.42	$ 0.27
Management Recognition Plan [Member]
Dilutive potential common shares:
Dilutive weighted average shares outstanding (in shares)	1,099	2,406
Recognition and Retention Plan [Member]
Dilutive potential common shares:
Dilutive weighted average shares outstanding (in shares)	14,952	10,366