Note 17 - Condensed Parent Only Financial Statements - Statements of Cash Flows (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Cash Flows from Operating Activities
Net income	$ 814,024	$ 1,261,098
Adjustments to reconcile net income to net cash provided by operating activities:
Increase in other assets	(679,346)	(503,535)
Net cash provided by operating activities	2,939,153	2,362,650
Cash Flows from Investing Activities
Net cash used in investing activities	(28,578,559)	(18,964,991)
Cash Flows from Financing Activities
Proceeds from stock offering including shares purchased by ESOP, net of expenses		22,337,869
Proceeds from stock options exercised	7,140	127,926
Shares repurchased and cancelled	(253,932)
Dividends paid	(523,426)
Loan to ESOP to purchase Company stock in stock offering		(1,907,160)
Net cash provided by financing activities	23,448,574	15,413,271
Net (decrease) increase in cash and cash equivalents	(2,190,832)	(1,189,070)
Cash and cash equivalents:
Beginning of period	5,946,649	7,135,719
End of period	3,755,817	5,946,649
Supplemental Disclosures of Cash Flow Information
Cash paid for taxes, net of refunds received	836,395
Supplemental Schedule of Noncash Investing and Financing Activities
Increase in ESOP put option liability	394,385	431,086
Parent Company [Member]
Cash Flows from Operating Activities
Net income	814,024	1,261,098
Adjustments to reconcile net income to net cash provided by operating activities:
Increase in other assets	(14,018)
Undistributed net income of subsidiary	(858,784)	(1,316,346)
Net cash provided by operating activities	(58,778)	(55,248)
Cash Flows from Investing Activities
Payments received on ESOP notes receivable	164,195	207,165
Net cash used in investing activities	164,195	207,165
Cash Flows from Financing Activities
Proceeds from stock offering including shares purchased by ESOP, net of expenses		22,337,869
Distribution of stock offering proceeds to bank		(11,106,092)
Proceeds from stock options exercised	7,140	127,926
Shares repurchased and cancelled	(253,932)
Dividends paid	(523,426)
Loan to ESOP to purchase Company stock in stock offering		(1,907,160)
Net cash provided by financing activities	(770,218)	9,452,543
Net (decrease) increase in cash and cash equivalents	(664,801)	9,604,460
Cash and cash equivalents:
Beginning of period	9,930,224	325,764
End of period	9,265,423	9,930,224
Supplemental Disclosures of Cash Flow Information
Cash paid for taxes, net of refunds received	(3,976)
Supplemental Schedule of Noncash Investing and Financing Activities
Increase in ESOP put option liability	$ 394,385	$ 431,086