Note 3 - Loans Receivable - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Total TDR loans	$ 1,843	$ 2,224
Total nonaccrual TDR loans	$ 29	$ 108
TDR loans that subsequently defaulted, number of contracts		0
Number of Contracts	0
Total accrual TDR loans	$ 1,814	$ 2,116
One-to-four Family Loan [Member] \| Real Estate Portfolio Segment [Member]
Total TDR loans	1,792	2,162
Total nonaccrual TDR loans	$ 29	$ 108
TDR loans that subsequently defaulted, number of contracts	1
TDR loans that subsequently defaulted, modifications	$ 29
Number of Contracts		1
Pre-modification outstanding recorded investment		$ 29
Post-modification outstanding recorded investment		29
Total accrual TDR loans	1,763	2,054
One-to-four Family Loan [Member] \| Real Estate Portfolio Segment [Member] \| Rate Modification [Member]
TDR loans that subsequently defaulted, modifications	29
Pre-modification outstanding recorded investment		29
Post-modification outstanding recorded investment		29
One-to-four Family Loan [Member] \| Real Estate Portfolio Segment [Member] \| Term Modification [Member]
TDR loans that subsequently defaulted, modifications	0
Pre-modification outstanding recorded investment		0
Post-modification outstanding recorded investment		0
One-to-four Family Loan [Member] \| Real Estate Portfolio Segment [Member] \| Combination Modification [Member]
TDR loans that subsequently defaulted, modifications	0
Pre-modification outstanding recorded investment		0
Post-modification outstanding recorded investment		0
Troubled Debt Restructurings [Member]
Allowance for loan losses related to TDR loans	21	26
Home Equity Loan [Member] \| Consumer Portfolio Segment [Member]
Total TDR loans	51	62
Total nonaccrual TDR loans	0	0
Total accrual TDR loans	$ 51	$ 62

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