Note 5 - Loans and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Balance, beginning of period	$ 7,607,587	$ 7,996,000
Provision for Loan Losses	500,000
Losses charged off	(94,000)	(288,000)
Recoveries	35,000	139,000
Balance, end of period	8,049,264	7,847,000
Ending balance: individually evaluated for impairment	1,148,000		$ 1,094,000
Ending balance: collectively evaluated for impairment	6,898,000		6,514,000
Ending balance: loans acquired with deteriorated credit quality	3,000
Ending balance: individually evaluated for impairment	8,614,000		9,133,000
Ending balance: collectively evaluated for impairment	718,363,000		716,946,000
Ending balance: loans acquired with deteriorated credit quality	2,821,000		2,835,000
Real Estate, Construction [Member]
Balance, beginning of period	1,749,000	2,306,000
Provision for Loan Losses	(120,000)	(490,000)
Losses charged off
Recoveries		120,000
Balance, end of period	1,629,000	1,936,000
Ending balance: individually evaluated for impairment	596,000		553,000
Ending balance: collectively evaluated for impairment	1,033,000		1,196,000
Ending balance: loans acquired with deteriorated credit quality
Ending balance: individually evaluated for impairment	4,424,000		4,742,000
Ending balance: collectively evaluated for impairment	68,690,000		72,567,000
Ending balance: loans acquired with deteriorated credit quality
Commercial Real Estate Portfolio Segment [Member]
Balance, beginning of period	2,267,000
Provision for Loan Losses	304,000
Losses charged off
Recoveries	6,000
Balance, end of period	2,577,000
Ending balance: individually evaluated for impairment	32,000		24,000
Ending balance: collectively evaluated for impairment	2,545,000		2,243,000
Ending balance: loans acquired with deteriorated credit quality
Ending balance: individually evaluated for impairment	807,000		650,000
Ending balance: collectively evaluated for impairment	297,255,000		297,318,000
Ending balance: loans acquired with deteriorated credit quality	2,643,000		2,651,000
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Balance, beginning of period		2,093,000
Provision for Loan Losses		43,000
Losses charged off
Recoveries		1,000
Balance, end of period		2,137,000
Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Balance, beginning of period	1,001,000	1,297,000
Provision for Loan Losses	152,000	85,000
Losses charged off
Recoveries	1,000	4,000
Balance, end of period	1,154,000	1,386,000
Ending balance: individually evaluated for impairment	184,000		197,000
Ending balance: collectively evaluated for impairment	970,000		804,000
Ending balance: loans acquired with deteriorated credit quality
Ending balance: individually evaluated for impairment	2,137,000		2,613,000
Ending balance: collectively evaluated for impairment	122,251,000		116,211,000
Ending balance: loans acquired with deteriorated credit quality
Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Balance, beginning of period	746,000	641,000
Provision for Loan Losses	9,000	53,000
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	755,000	694,000
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	755,000		746,000
Ending balance: loans acquired with deteriorated credit quality
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	82,549,000		87,448,000
Ending balance: loans acquired with deteriorated credit quality
Commercial Portfolio Segment [Member]
Balance, beginning of period	1,129,000	1,160,000
Provision for Loan Losses	237,000	39,000
Losses charged off	(32,000)	(234,000)
Recoveries	15,000	9,000
Balance, end of period	1,349,000	974,000
Ending balance: individually evaluated for impairment	311,000		299,000
Ending balance: collectively evaluated for impairment	1,035,000		830,000
Ending balance: loans acquired with deteriorated credit quality	3,000
Ending balance: individually evaluated for impairment	943,000		908,000
Ending balance: collectively evaluated for impairment	117,060,000		112,956,000
Ending balance: loans acquired with deteriorated credit quality	178,000		184,000
Consumer and Other Loans [Member]
Ending balance: individually evaluated for impairment	25,000		21,000
Ending balance: collectively evaluated for impairment	424,000		422,000
Ending balance: loans acquired with deteriorated credit quality
Ending balance: individually evaluated for impairment	303,000		220,000
Ending balance: collectively evaluated for impairment	30,558,000		30,446,000
Ending balance: loans acquired with deteriorated credit quality
Consumer Portfolio Segment [Member]
Balance, beginning of period	443,000	373,000
Provision for Loan Losses	55,000	44,000
Losses charged off	(62,000)	(54,000)
Recoveries	13,000	5,000
Balance, end of period	449,000	368,000
Unallocated Financing Receivables [Member]
Balance, beginning of period	273,000	126,000
Provision for Loan Losses	(137,000)	226,000
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	136,000	$ 352,000
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	136,000		273,000
Ending balance: loans acquired with deteriorated credit quality
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment
Ending balance: loans acquired with deteriorated credit quality