Note 4 - Loans and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Balance, beginning of period	$ 6,172,000	$ 6,185,000	$ 5,742,449	$ 5,812,000
Provision for loan losses	575,000	375,000	1,050,000	750,000
Losses charged off	(138,000)	(503,000)	(219,000)	(532,000)
Recoveries	31,000	124,000	67,000	151,000
Balance, end of period	6,640,164	6,181,000	6,640,164	6,181,000
Ending balance: collectively evaluated for impairment	5,866,000		5,866,000		$ 5,140,000
Loans:
Ending balance: individually evaluated for impairment	8,579,000		8,579,000		8,699,000
Ending balance: collectively evaluated for impairment	606,736,000		606,736,000		535,699,000
Ending balance: individually evaluated for impairment	774,000		774,000		602,000
Residential Portfolio Segment [Member] | Construction Loans [Member]
Balance, beginning of period	1,299,000	1,868,000	1,377,000	1,246,000
Provision for loan losses	142,000	19,000	46,000	640,000
Losses charged off		(252,000)		(252,000)
Recoveries	21,000	33,000	39,000	34,000
Balance, end of period	1,462,000	1,668,000	1,462,000	1,668,000
Ending balance: collectively evaluated for impairment	1,185,000		1,185,000		1,075,000
Loans:
Ending balance: individually evaluated for impairment	5,364,000		5,364,000		5,447,000
Ending balance: collectively evaluated for impairment	51,448,000		51,448,000		35,465,000
Ending balance: individually evaluated for impairment	277,000		277,000		302,000
Residential Portfolio Segment [Member] | One To Four Family Units [Member]
Balance, beginning of period	818,000	826,000	856,000	821,000
Provision for loan losses	51,000	77,000	18,000	74,000
Losses charged off		(47,000)	(11,000)	(47,000)
Recoveries	2,000	6,000	8,000	14,000
Balance, end of period	871,000	862,000	871,000	862,000
Ending balance: collectively evaluated for impairment	806,000		806,000		842,000
Loans:
Ending balance: individually evaluated for impairment	1,848,000		1,848,000		2,060,000
Ending balance: collectively evaluated for impairment	104,525,000		104,525,000		104,351,000
Ending balance: individually evaluated for impairment	65,000		65,000		14,000
Residential Portfolio Segment [Member] | Multi Family Units [Member]
Balance, beginning of period	273,000	159,000	206,000	177,000
Provision for loan losses	50,000	(2,000)	117,000	(20,000)
Losses charged off	0		0
Recoveries	0		0
Balance, end of period	323,000	157,000	323,000	157,000
Ending balance: collectively evaluated for impairment	323,000		323,000		206,000
Loans:
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment	76,025,000		76,025,000		48,483,000
Ending balance: individually evaluated for impairment
Commercial Real Estate Portfolio Segment [Member]
Ending balance: collectively evaluated for impairment	1,768,000		1,768,000		1,687,000
Loans:
Ending balance: individually evaluated for impairment	328,000		328,000		161,000
Ending balance: collectively evaluated for impairment	262,887,000		262,887,000		249,420,000
Ending balance: individually evaluated for impairment	93,000		93,000
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Balance, beginning of period	1,742,000	1,486,000	1,687,000	1,526,000
Provision for loan losses	119,000	101,000	174,000	55,000
Losses charged off
Recoveries		26,000		32,000
Balance, end of period	1,861,000	1,613,000	1,861,000	1,613,000
Commercial Portfolio Segment [Member]
Balance, beginning of period	883,000	1,503,000	1,168,000	1,382,000
Provision for loan losses	99,000	21,000	(188,000)	142,000
Losses charged off	(85,000)	(159,000)	(85,000)	(159,000)
Recoveries	2,000	1,000	4,000	1,000
Balance, end of period	899,000	1,366,000	899,000	1,366,000
Ending balance: collectively evaluated for impairment	572,000		572,000		927,000
Loans:
Ending balance: individually evaluated for impairment	975,000		975,000		925,000
Ending balance: collectively evaluated for impairment	86,056,000		86,056,000		74,480,000
Ending balance: individually evaluated for impairment	327,000		327,000		241,000
Consumer Portfolio Segment [Member] | Other Loans [Member]
Balance, beginning of period	282,000	270,000	337,000	223,000
Provision for loan losses	88,000	5,000	93,000	69,000
Losses charged off	(53,000)	(45,000)	(123,000)	(74,000)
Recoveries	6,000	58,000	16,000	70,000
Balance, end of period	323,000	288,000	323,000	288,000
Ending balance: collectively evaluated for impairment	311,000		311,000		292,000
Loans:
Ending balance: individually evaluated for impairment	64,000		64,000		106,000
Ending balance: collectively evaluated for impairment	25,795,000		25,795,000		23,500,000
Ending balance: individually evaluated for impairment	12,000		12,000		45,000
Unallocated [Member]
Balance, beginning of period	875,000	73,000	111,000	437,000
Provision for loan losses	26,000	154,000	790,000	(210,000)
Losses charged off	0		0
Recoveries	0		0
Balance, end of period	901,000	$ 227,000	901,000	$ 227,000
Unallocated Financing Receivables [Member]
Ending balance: collectively evaluated for impairment	901,000		901,000		111,000
Loans:
Ending balance: individually evaluated for impairment
Ending balance: collectively evaluated for impairment
Ending balance: individually evaluated for impairment