Note 13 - Fair Value of Financial Instruments - Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Jun. 30, 2021
Cash and cash equivalents	$ 2,948	$ 2,551
Certificates of deposit	350	350
Investment securities - held to maturity	9,953	15,489
Net loans receivable	78,526	80,684
Accrued interest receivable	746	749
FHLB stock	6,264	6,044
Bank owned life insurance	5,077	5,021
Non-interest bearing deposits	26,923	25,452
Savings accounts	49,568	50,058
Money market accounts	22,529	22,995
FHLB advances – fixed rate	153,600	148,093
FHLB short-term advances	148,600	113,093
Accrued interest payable	92	155
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities - held to maturity	112,463	82,059
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Investment securities - held to maturity	334	400
Reported Value Measurement [Member]
Cash and cash equivalents	2,948	2,551
Certificates of deposit	350	350
Investment securities - held to maturity	9,953	15,489
Net loans receivable	78,526	80,684
Accrued interest receivable	746	749
FHLB stock	6,264	6,044
Bank owned life insurance	5,077	5,021
Non-interest bearing deposits	26,923	25,452
Interest-earning checking	27,896	26,881
Savings accounts	49,568	50,058
Money market accounts	22,529	22,995
Certificates of deposit	33,096	29,731
Advance payments by borrowers for taxes and insurance	1,373	2,050
FHLB advances – fixed rate	5,000	10,000
FHLB advances – variable rate	0	25,000
FHLB short-term advances	148,600	113,093
Accrued interest payable	92	155
Reported Value Measurement [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities - held to maturity	112,463	82,059
Reported Value Measurement [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
Investment securities - held to maturity	334	400
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	2,948	2,551
Certificates of deposit	350	350
Investment securities - held to maturity	9,978	15,592
Net loans receivable	80,449	82,930
Accrued interest receivable	746	749
FHLB stock	6,264	6,044
Bank owned life insurance	5,077	5,021
Non-interest bearing deposits	26,923	25,452
Interest-earning checking	27,896	26,881
Savings accounts	49,568	50,058
Money market accounts	22,529	22,995
Certificates of deposit	33,453	29,763
Advance payments by borrowers for taxes and insurance	1,373	2,050
FHLB advances – fixed rate	5,049	9,763
FHLB advances – variable rate	0	25,000
FHLB short-term advances	148,600	113,093
Accrued interest payable	92	155
Estimate of Fair Value Measurement [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities - held to maturity	112,675	82,202
Estimate of Fair Value Measurement [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
Investment securities - held to maturity	408	457
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	2,948	2,551
Certificates of deposit	350	350
Investment securities - held to maturity	0	0
Net loans receivable	0	0
Accrued interest receivable	746	749
FHLB stock	6,264	6,044
Bank owned life insurance	5,077	5,021
Non-interest bearing deposits	26,923	25,452
Interest-earning checking	27,896	26,881
Savings accounts	49,568	50,058
Money market accounts	22,529	22,995
Certificates of deposit	0	0
Advance payments by borrowers for taxes and insurance	1,373	2,050
FHLB advances – fixed rate	0	0
FHLB advances – variable rate	0	25,000
FHLB short-term advances	148,600	113,093
Accrued interest payable	92	155
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities - held to maturity	0	0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
Investment securities - held to maturity	0	0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Certificates of deposit	0	0
Investment securities - held to maturity	9,978	15,592
Net loans receivable	0	0
Accrued interest receivable	0	0
FHLB stock	0	0
Bank owned life insurance	0	0
Non-interest bearing deposits	0	0
Interest-earning checking	0	0
Savings accounts	0	0
Money market accounts	0	0
Certificates of deposit	0	0
Advance payments by borrowers for taxes and insurance	0	0
FHLB advances – fixed rate	0	0
FHLB advances – variable rate	0	0
FHLB short-term advances	0	0
Accrued interest payable	0	0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities - held to maturity	112,675	82,202
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
Investment securities - held to maturity	0	0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Certificates of deposit	0	0
Investment securities - held to maturity	0	0
Net loans receivable	80,449	82,930
Accrued interest receivable	0	0
FHLB stock	0	0
Bank owned life insurance	0	0
Non-interest bearing deposits	0	0
Interest-earning checking	0	0
Savings accounts	0	0
Money market accounts	0	0
Certificates of deposit	33,453	29,763
Advance payments by borrowers for taxes and insurance	0	0
FHLB advances – fixed rate	5,049	9,763
FHLB advances – variable rate	0	0
FHLB short-term advances	0	0
Accrued interest payable	0	0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities - held to maturity	0	0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
Investment securities - held to maturity	$ 408	$ 457