Note 20 - Condensed Financial Statements of Parent Company - Statements of Cash Flows (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities
Net income	$ 360,591	$ 5,295,127
Changes in operating assets and liabilities:
Prepaid and other assets	(638,832)	204,641
Net cash (used for) operating activities	15,425,685	6,920,133
Cash flows from investing activities
Net cash provided by investing activities	(27,625,768)	(62,129,562)
Cash flows from financing activities
Issuance of common stock	55,314	15,936,416
Common stock repurchases	(414,400)	0
Net cash (used for) provided by financing activities	5,661,917	51,795,909
Net increase (decrease) in cash and due from banks	(6,538,166)	(3,413,520)
Cash and cash equivalents, beginning of period	16,411,344	19,824,864
Cash and cash equivalents, end of period	9,873,178	16,411,344
Parent Company [Member]
Cash flows from operating activities
Net income	360,591	5,295,127
Adjustments to reconcile net income to net cash from operating activities:
Equity in (income) of subsidiary	(643,113)	(4,847,989)
Changes in operating assets and liabilities:
Income taxes payable	(29,472)	(645,924)
Prepaid and other assets	116,081	(437,160)
Accrued interest and other liabilities	35,827	(15,421)
Other, net	0	0
Net cash (used for) operating activities	(160,086)	(651,367)
Cash flows from investing activities
Principal collections on ESOP note receivable	30,134	30,707
Net cash provided by investing activities	30,134	30,707
Cash flows from financing activities
Issuance of common stock	55,314	0
Common stock repurchases	(414,400)	0
Second-step conversion proceeds	0	18,794,840
ESOP shares purchased	0	(1,503,580)
Conversion costs	0	(1,363,693)
Capital injection into subsidiary	0	(8,722,655)
Net cash (used for) provided by financing activities	(359,086)	7,204,912
Net increase (decrease) in cash and due from banks	(489,038)	6,584,252
Cash and cash equivalents, beginning of period	6,978,326	394,074
Cash and cash equivalents, end of period	$ 6,489,288	$ 6,978,326