Loans - Credit quality indicators (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	$ 476,516	$ 479,669
Residential and Consumer Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	190,309	196,663
Residential and Consumer Loan | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	187,086	191,424
Residential and Consumer Loan | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	3,223	5,239
Commercial Loan Total
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	286,207	283,006
Commercial Loan Total | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	282,970	279,923
Commercial Loan Total | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	1,662	1,773
Commercial Loan Total | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	1,575	1,310
Residential real estate | 1-4 Family
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	144,290	147,061
Residential real estate | Home equity and HELOCs
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	32,235	32,529
Residential real estate | Construction Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	11,630	14,834
Residential real estate | Residential and Consumer Loan | 1-4 Family
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	144,290	147,061
Residential real estate | Residential and Consumer Loan | 1-4 Family | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	141,372	142,280
Residential real estate | Residential and Consumer Loan | 1-4 Family | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	2,918	4,781
Residential real estate | Residential and Consumer Loan | Home equity and HELOCs
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	32,235	32,529
Residential real estate | Residential and Consumer Loan | Home equity and HELOCs | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	32,046	32,188
Residential real estate | Residential and Consumer Loan | Home equity and HELOCs | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	189	341
Residential real estate | Residential and Consumer Loan | Construction Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	11,630	14,834
Residential real estate | Residential and Consumer Loan | Construction Residential | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	11,630	14,834
Commercial real estate | 1 - 4 family investor
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	94,794	96,850
Commercial real estate | 1 - 4 family investor | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	93,322	95,271
Commercial real estate | 1 - 4 family investor | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	1,373	1,473
Commercial real estate | 1 - 4 family investor | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	99	106
Commercial real estate | Multi-family (five or more)
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	14,922	13,069
Commercial real estate | Multi-family (five or more) | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	14,631	12,778
Commercial real estate | Multi-family (five or more) | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	291	291
Commercial real estate | Commercial non-residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	157,606	158,727
Commercial real estate | Commercial non-residential | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	156,132	157,514
Commercial real estate | Commercial non-residential | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	289	300
Commercial real estate | Commercial non-residential | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	1,185	913
Commercial real estate | Construction and Land
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	7,953	4,951
Commercial real estate | Construction and Land | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	7,953	4,951
Commercial real estate | Construction and Land | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	0
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	10,932	9,409
Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	10,932	9,409
Commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	0
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	2,154	2,239
Consumer | Residential and Consumer Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	2,154	2,239
Consumer | Residential and Consumer Loan | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	2,038	2,122
Consumer | Residential and Consumer Loan | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	$ 116	$ 117