Note 13 - Fair Value of Financial Instruments - Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Jun. 30, 2021
Cash and cash equivalents	$ 3,323	$ 2,551
Certificates of deposit	350	350
Investment securities - held to maturity	9,954	15,489
Net loans receivable	76,166	80,684
Accrued interest receivable	987	749
FHLB stock	6,793	6,044
Bank owned life insurance	5,104	5,021
Non-interest bearing deposits	27,741	25,452
Interest-earning checking	28,148	26,881
Savings accounts	50,293	50,058
Money market accounts	24,062	22,995
FHLB advances – fixed rate	166,823	148,093
FHLB short-term advances	161,823	113,093
Accrued interest payable	114	155
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities - held to maturity	129,054	82,059
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Investment securities - held to maturity	359	400
Reported Value Measurement [Member]
Cash and cash equivalents	3,323	2,551
Certificates of deposit	350	350
Investment securities - held to maturity	9,954	15,489
Net loans receivable	76,166	80,684
Accrued interest receivable	987	749
FHLB stock	6,793	6,044
Bank owned life insurance	5,104	5,021
Non-interest bearing deposits	27,741	25,452
Interest-earning checking	28,148	26,881
Savings accounts	50,293	50,058
Money market accounts	24,062	22,995
Certificates of deposit	29,972	29,731
Advance payments by borrowers for taxes and insurance	1,460	2,050
FHLB advances – fixed rate	5,000	10,000
FHLB advances – variable rate	0	25,000
FHLB short-term advances	161,823	113,093
Accrued interest payable	114	155
Reported Value Measurement [Member] | Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities - held to maturity	129,054	82,059
Reported Value Measurement [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Investment securities - held to maturity	359	400
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	3,323	2,551
Certificates of deposit	350	350
Investment securities - held to maturity	9,545	15,592
Net loans receivable	75,035	82,930
Accrued interest receivable	987	749
FHLB stock	6,793	6,044
Bank owned life insurance	5,104	5,021
Non-interest bearing deposits	27,741	25,452
Interest-earning checking	28,148	26,881
Savings accounts	50,293	50,058
Money market accounts	24,062	22,995
Certificates of deposit	29,856	29,763
Advance payments by borrowers for taxes and insurance	1,460	2,050
FHLB advances – fixed rate	5,016	9,763
FHLB advances – variable rate	0	25,000
FHLB short-term advances	161,823	113,093
Accrued interest payable	114	155
Estimate of Fair Value Measurement [Member] | Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities - held to maturity	125,502	82,202
Estimate of Fair Value Measurement [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Investment securities - held to maturity	422	457
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	3,323	2,551
Certificates of deposit	350	350
Investment securities - held to maturity	0	0
Net loans receivable	0	0
Accrued interest receivable	987	749
FHLB stock	6,793	6,044
Bank owned life insurance	5,104	5,021
Non-interest bearing deposits	27,741	25,452
Interest-earning checking	28,148	26,881
Savings accounts	50,293	50,058
Money market accounts	24,062	22,995
Certificates of deposit	0	0
Advance payments by borrowers for taxes and insurance	1,460	2,050
FHLB advances – fixed rate	0	0
FHLB advances – variable rate	0	25,000
FHLB short-term advances	161,823	113,093
Accrued interest payable	114	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	9,545	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	125,502	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	75,035	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	29,856	29,763
Advance payments by borrowers for taxes and insurance	0	0
FHLB advances – fixed rate	5,016	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	$ 422	$ 457