Loans - Credit quality indicators (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Jun. 30, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	$ 479,669	$ 465,629
Residential and Consumer Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	196,663	224,599
Residential and Consumer Loan | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	191,424	220,362
Residential and Consumer Loan | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	5,239	4,237
Commercial Loan Total
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	283,006	241,030
Commercial Loan Total | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	279,923	237,556
Commercial Loan Total | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	1,773	2,410
Commercial Loan Total | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	1,310	1,064
Residential real estate | 1-4 Family
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	147,061	173,306
Residential real estate | 1-4 Family | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	1,700
Residential real estate | Home equity and HELOCs
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	32,529	37,222
Residential real estate | Construction Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	14,834	10,841
Residential real estate | Residential and Consumer Loan | 1-4 Family
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	147,061	173,306
Residential real estate | Residential and Consumer Loan | 1-4 Family | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	142,280	169,532
Residential real estate | Residential and Consumer Loan | 1-4 Family | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	4,781	3,774
Residential real estate | Residential and Consumer Loan | Home equity and HELOCs
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	32,529	37,222
Residential real estate | Residential and Consumer Loan | Home equity and HELOCs | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	32,188	36,877
Residential real estate | Residential and Consumer Loan | Home equity and HELOCs | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	341	345
Residential real estate | Residential and Consumer Loan | Construction Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	14,834	10,841
Residential real estate | Residential and Consumer Loan | Construction Residential | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	14,834	10,841
Commercial real estate | 1 - 4 family investor
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	96,850	120,581
Commercial real estate | 1 - 4 family investor | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	95,271	118,175
Commercial real estate | 1 - 4 family investor | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	1,473	2,054
Commercial real estate | 1 - 4 family investor | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	106	352
Commercial real estate | Multi-family (five or more)
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	13,069	12,315
Commercial real estate | Multi-family (five or more) | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	12,778	12,139
Commercial real estate | Multi-family (five or more) | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	291	176
Commercial real estate | Commercial non-residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	158,727	96,612
Commercial real estate | Commercial non-residential | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	157,514	95,720
Commercial real estate | Commercial non-residential | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	300	356
Commercial real estate | Commercial non-residential | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	913	536
Commercial real estate | Construction and Land
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	4,951	6,377
Commercial real estate | Construction and Land | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	4,951	6,377
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	9,409	5,145
Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	9,409	5,145
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	2,239	3,230
Consumer | Residential and Consumer Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	2,239	3,230
Consumer | Residential and Consumer Loan | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	2,122	3,112
Consumer | Residential and Consumer Loan | Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	$ 117	$ 118