Note 4 - Loans and Allowance for Loan Losses - Loans by Aging (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Loans receivable, past due	$ 1,356,000	$ 10,554,000
Loans receivable, current	727,558,000	776,341,000
Loans receivable	728,914,025	786,894,894
Loans receivable, past due and accruing
Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Loans receivable, past due	645,000	2,670,000
Loans receivable, current	118,179,000	129,741,000
Loans receivable	118,823,731	132,410,810
Loans receivable, past due and accruing
Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Loans receivable, past due		5,952,000
Loans receivable, current	87,448,000	84,596,000
Loans receivable	87,448,418	90,548,265
Loans receivable, past due and accruing
Real Estate, Construction [Member]
Loans receivable, past due	338,000
Loans receivable, current	76,971,000	88,554,000
Loans receivable	77,308,551	88,553,995
Loans receivable, past due and accruing
Commercial Real Estate Portfolio Segment [Member]
Loans receivable, past due	43,000	1,081,000
Loans receivable, current	300,576,000	321,840,000
Loans receivable	300,619,387	322,921,323
Loans receivable, past due and accruing
Commercial Portfolio Segment [Member]
Loans receivable, past due	256,000	732,000
Loans receivable, current	113,792,000	118,638,000
Loans receivable	114,047,753	119,369,484
Loans receivable, past due and accruing
Consumer and Other Loans [Member]
Loans receivable, past due	74,000	119,000
Loans receivable, current	30,592,000	32,972,000
Loans receivable	30,666,185	33,091,017
Loans receivable, past due and accruing
Financial Asset, 30 to 59 Days Past Due [Member]
Loans receivable, past due	603,000	7,464,000
Financial Asset, 30 to 59 Days Past Due [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Loans receivable, past due	83,000	177,000
Financial Asset, 30 to 59 Days Past Due [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Loans receivable, past due		5,952,000
Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate, Construction [Member]
Loans receivable, past due	338,000
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans receivable, past due		1,000,000
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Loans receivable, past due	134,000	228,000
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer and Other Loans [Member]
Loans receivable, past due	48,000	107,000
Financial Asset, 60 to 89 Days Past Due [Member]
Loans receivable, past due	568,000	855,000
Financial Asset, 60 to 89 Days Past Due [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Loans receivable, past due	437,000	329,000
Financial Asset, 60 to 89 Days Past Due [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Loans receivable, past due
Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate, Construction [Member]
Loans receivable, past due
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans receivable, past due		81,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Loans receivable, past due	105,000	433,000
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer and Other Loans [Member]
Loans receivable, past due	26,000	12,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable, past due	185,000	2,235,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Loans receivable, past due	125,000	2,164,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential Portfolio Segment [Member] | Real Estate Residential, Multi Family Units [Member]
Loans receivable, past due
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate, Construction [Member]
Loans receivable, past due
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member]
Loans receivable, past due	43,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Loans receivable, past due	17,000	71,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer and Other Loans [Member]
Loans receivable, past due