Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Valuation allowance	$ 851	$ 421
Loans with a specific valuation allowance, recorded balance	10,008	19,014
Loans unpaid principal	10,044	20,985
Loans average investment in impaired loans	13,372	11,908
Loans interest income recognized	10	17
Residential Portfolio Segment [Member] | Real Estate Residential, One To Four Family Units [Member]
Loans without a specific valuation allowance, recorded balance	1,347	2,780
Loans without a specific valuation allowance, unpaid principal	1,347	2,780
Loans without a specific valuation allowance, interest income recognized	1,868	1,199
Loans with a specific valuation allowance, recorded balance	105	330
Loans with a specific valuation allowance, unpaid principal	105	330
Valuation allowance	49	112
Loans with a specific valuation allowance, average investment in impaired loans	145	1,183
Loans with a specific valuation allowance, recorded balance	1,452	3,110
Loans unpaid principal	1,452	3,110
Loans average investment in impaired loans	2,013	2,382
Real Estate, Construction [Member]
Loans without a specific valuation allowance, recorded balance	2,025	5,081
Loans without a specific valuation allowance, unpaid principal	2,025	5,081
Loans without a specific valuation allowance, interest income recognized	3,285	423
Loans with a specific valuation allowance, recorded balance	866	1,158
Loans with a specific valuation allowance, unpaid principal	866	3,129
Valuation allowance	656	114
Loans with a specific valuation allowance, average investment in impaired loans	891	4,093
Loans with a specific valuation allowance, recorded balance	2,891	6,239
Loans unpaid principal	2,891	8,210
Loans average investment in impaired loans	4,176	4,516
Commercial Real Estate Portfolio Segment [Member]
Loans without a specific valuation allowance, recorded balance	2,976	3,419
Loans without a specific valuation allowance, unpaid principal	2,976	3,419
Loans without a specific valuation allowance, interest income recognized	3,269	3,152
Loans with a specific valuation allowance, interest income recognized	10	4
Loans with a specific valuation allowance, recorded balance	494	801
Loans with a specific valuation allowance, unpaid principal	494	801
Valuation allowance	85	117
Loans with a specific valuation allowance, average investment in impaired loans	602	365
Loans with a specific valuation allowance, recorded balance	3,470	4,220
Loans unpaid principal	3,470	4,220
Loans average investment in impaired loans	3,871	3,517
Loans interest income recognized	10	4
Commercial Portfolio Segment [Member]
Loans without a specific valuation allowance, recorded balance	1,837	4,902
Loans without a specific valuation allowance, unpaid principal	1,837	4,902
Loans without a specific valuation allowance, interest income recognized	2,808	455
Loans with a specific valuation allowance, recorded balance	187	341
Loans with a specific valuation allowance, unpaid principal	223	341
Valuation allowance	46	63
Loans with a specific valuation allowance, average investment in impaired loans	313	792
Loans with a specific valuation allowance, recorded balance	2,024	5,243
Loans unpaid principal	2,060	5,243
Loans average investment in impaired loans	3,121	1,247
Consumer and Other Loans [Member]
Loans without a specific valuation allowance, recorded balance	89	100
Loans without a specific valuation allowance, unpaid principal	89	100
Loans without a specific valuation allowance, interest income recognized	97	110
Loans with a specific valuation allowance, interest income recognized		13
Loans with a specific valuation allowance, recorded balance	82	102
Loans with a specific valuation allowance, unpaid principal	82	102
Valuation allowance	15	15
Loans with a specific valuation allowance, average investment in impaired loans	94	136
Loans with a specific valuation allowance, recorded balance	171	202
Loans unpaid principal	171	202
Loans average investment in impaired loans	$ 191	246
Loans interest income recognized		$ 13