Note 7 - Fair Value - Carrying Amount and Fair Value of Financial Instruments Included in the Consolidated Balance Sheet (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Debt securities, fair value	$ 183,675,000	$ 113,041,000
Securities - equities	9,000	15,000
Loans held for sale	0	75,000
Federal bank stock	5,846,000	5,635,000
Fair Value, Inputs, Level 1 [Member]
Debt securities, fair value	0	0
Securities - equities	9,000	15,000
Fair Value, Inputs, Level 2 [Member]
Debt securities, fair value	181,669,000	111,035,000
Securities - equities	0	0
Fair Value, Inputs, Level 3 [Member]
Debt securities, fair value	2,006,000	2,006,000
Securities - equities	0	0
Reported Value Measurement [Member]
Cash and cash equivalents	50,518,000	37,439,000
Interest earning time deposits	3,480,000	5,718,000
Debt securities, fair value	183,675,000	113,041,000
Securities - equities	9,000	15,000
Loans held for sale	0	75,000
Loans, net	794,291,000	800,338,000
Federal bank stock	5,846,000	5,635,000
Accrued interest receivable	4,140,000	3,786,000
Deposits	959,319,000	893,627,000
Borrowed funds	32,050,000	32,050,000
Accrued interest payable	448,000	474,000
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	50,518,000	37,439,000
Interest earning time deposits	3,480,000	5,718,000
Debt securities, fair value	183,675,000	113,041,000
Securities - equities	9,000	15,000
Loans held for sale	0	75,000
Loans, net	794,221,000	807,170,000
Accrued interest receivable	4,140,000	3,786,000
Deposits	963,294,000	899,446,000
Borrowed funds	32,484,000	33,256,000
Accrued interest payable	448,000	474,000
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	50,518,000	37,439,000
Interest earning time deposits	0	0
Debt securities, fair value	0	0
Securities - equities	9,000	15,000
Loans held for sale	0	0
Loans, net	0	0
Accrued interest receivable	38,000	52,000
Deposits	780,222,000	705,680,000
Borrowed funds	0	0
Accrued interest payable	9,000	19,000
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Interest earning time deposits	3,480,000	5,718,000
Debt securities, fair value	181,669,000	111,035,000
Securities - equities	0	0
Loans held for sale	0	75,000
Loans, net	0	0
Accrued interest receivable	766,000	513,000
Deposits	183,072,000	193,766,000
Borrowed funds	32,484,000	33,256,000
Accrued interest payable	439,000	455,000
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Interest earning time deposits	0	0
Debt securities, fair value	2,006,000	2,006,000
Securities - equities	0	0
Loans held for sale	0	0
Loans, net	794,221,000	807,170,000
Accrued interest receivable	3,336,000	3,221,000
Deposits	0	0
Borrowed funds	0	0
Accrued interest payable	$ 0	$ 0