Loans - Credit quality indicators (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Jun. 30, 2023
Term Loans Amortized Cost Basis by Origination Year
Total	$ 470,815	$ 470,815
Current period gross charge-offs
Total	13	13
Total Loans			$ 480,856
Residential and Consumer Loan
Current period gross charge-offs
Total Loans			178,843
Residential and Consumer Loan | Performing
Current period gross charge-offs
Total Loans			176,671
Residential and Consumer Loan | Nonperforming
Current period gross charge-offs
Total Loans			2,172
Commercial Loan Total
Current period gross charge-offs
Total Loans			302,013
Commercial Loan Total | Pass
Current period gross charge-offs
Total Loans			298,921
Commercial Loan Total | Special Mention
Current period gross charge-offs
Total Loans			1,231
Commercial Loan Total | Substandard
Current period gross charge-offs
Total Loans			1,861
Residential real estate | 1-4 Family
Term Loans Amortized Cost Basis by Origination Year
2024	6,302	6,302
2023	7,939	7,939
2022	13,680	13,680
2021	15,611	15,611
2020	8,629	8,629
Prior	77,509	77,509
Total	129,670	129,670
Current period gross charge-offs
Total Loans			135,046
Residential real estate | 1-4 Family | Performing
Term Loans Amortized Cost Basis by Origination Year
2024	6,302	6,302
2023	7,939	7,939
2022	13,680	13,680
2021	15,611	15,611
2020	8,629	8,629
Prior	76,029	76,029
Total	128,190	128,190
Current period gross charge-offs
Total Loans			132,956
Residential real estate | 1-4 Family | Nonperforming
Term Loans Amortized Cost Basis by Origination Year
Prior	1,480	1,480
Total	1,480	1,480
Current period gross charge-offs
Total Loans			2,090
Residential real estate | Home equity and HELOCs
Term Loans Amortized Cost Basis by Origination Year
2024	822	822
2023	2,289	2,289
2022	503	503
2021	947	947
2020	723	723
Prior	5,262	5,262
Revolving Loans Amortized Cost Basis	19,016	19,016
Revolving Loans Converted to Term	1,620	1,620
Total	31,182	31,182
Current period gross charge-offs
Total Loans			32,684
Residential real estate | Home equity and HELOCs | Performing
Term Loans Amortized Cost Basis by Origination Year
2024	822	822
2023	2,289	2,289
2022	503	503
2021	947	947
2020	723	723
Prior	5,262	5,262
Revolving Loans Amortized Cost Basis	19,000	19,000
Revolving Loans Converted to Term	1,620	1,620
Total	31,166	31,166
Current period gross charge-offs
Total Loans			32,684
Residential real estate | Home equity and HELOCs | Nonperforming
Term Loans Amortized Cost Basis by Origination Year
Revolving Loans Amortized Cost Basis	16	16
Total	16	16
Residential real estate | Construction Residential
Term Loans Amortized Cost Basis by Origination Year
2024	2,465	2,465
2023	5,204	5,204
2022	689	689
2021	1,541	1,541
Total	9,899	9,899
Current period gross charge-offs
Total Loans			9,113
Residential real estate | Construction Residential | Performing
Term Loans Amortized Cost Basis by Origination Year
2024	2,465	2,465
2023	5,204	5,204
2022	689	689
2021	1,541	1,541
Total	9,899	9,899
Current period gross charge-offs
Total Loans			9,113
Commercial real estate
Term Loans Amortized Cost Basis by Origination Year
Total	52,700	52,700
Commercial real estate | 1-4 Family
Term Loans Amortized Cost Basis by Origination Year
Total	94,336	94,336
Commercial real estate | 1 - 4 family investor
Term Loans Amortized Cost Basis by Origination Year
2024	2,386	2,386
2023	12,103	12,103
2022	6,752	6,752
2021	17,021	17,021
2020	12,116	12,116
Prior	41,304	41,304
Revolving Loans Amortized Cost Basis	1,940	1,940
Revolving Loans Converted to Term	714	714
Total	94,336	94,336
Current period gross charge-offs
Total Loans			98,160
Commercial real estate | 1 - 4 family investor | Pass
Term Loans Amortized Cost Basis by Origination Year
2024	2,386	2,386
2023	12,103	12,103
2022	6,752	6,752
2021	17,021	17,021
2020	12,116	12,116
Prior	40,132	40,132
Revolving Loans Amortized Cost Basis	1,940	1,940
Revolving Loans Converted to Term	714	714
Total	93,164	93,164
Current period gross charge-offs
Total Loans			96,097
Commercial real estate | 1 - 4 family investor | Special Mention
Term Loans Amortized Cost Basis by Origination Year
Prior	1,070	1,070
Total	1,070	1,070
Current period gross charge-offs
Total Loans			1,231
Commercial real estate | 1 - 4 family investor | Substandard
Term Loans Amortized Cost Basis by Origination Year
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior	102	102
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term	0	0
Total	102	102
Current period gross charge-offs
Total Loans			832
Commercial real estate | Multi-family (five or more)
Term Loans Amortized Cost Basis by Origination Year
2024	101	101
2023	1,174	1,174
2022	1,334	1,334
2021	4,143	4,143
2020	5,015	5,015
Prior	3,339	3,339
Total	15,106	15,106
Current period gross charge-offs
Total Loans			15,281
Commercial real estate | Multi-family (five or more) | Pass
Term Loans Amortized Cost Basis by Origination Year
2024	101	101
2023	1,174	1,174
2022	1,334	1,334
2021	4,143	4,143
2020	5,015	5,015
Prior	3,116	3,116
Total	14,883	14,883
Current period gross charge-offs
Total Loans			15,030
Commercial real estate | Multi-family (five or more) | Substandard
Term Loans Amortized Cost Basis by Origination Year
Prior	223	223
Total	223	223
Current period gross charge-offs
Total Loans			251
Commercial real estate | Commercial non-residential
Term Loans Amortized Cost Basis by Origination Year
2024	1,015	1,015
2023	21,957	21,957
2022	62,131	62,131
2021	30,709	30,709
2020	16,746	16,746
Prior	21,235	21,235
Revolving Loans Converted to Term	93	93
Total	153,886	153,886
Current period gross charge-offs
Total Loans			157,555
Commercial real estate | Commercial non-residential | Pass
Term Loans Amortized Cost Basis by Origination Year
2024	1,015	1,015
2023	21,957	21,957
2022	62,131	62,131
2021	30,390	30,390
2020	16,273	16,273
Prior	20,942	20,942
Revolving Loans Converted to Term	93	93
Total	152,801	152,801
Current period gross charge-offs
Total Loans			156,777
Commercial real estate | Commercial non-residential | Substandard
Term Loans Amortized Cost Basis by Origination Year
2021	319	319
2020	473	473
Prior	293	293
Total	1,085	1,085
Current period gross charge-offs
Total Loans			778
Commercial real estate | Construction and land
Term Loans Amortized Cost Basis by Origination Year
2024	813	813
2023	5,377	5,377
2022	10,501	10,501
2020	1,164	1,164
Prior	2,098	2,098
Total	19,953	19,953
Current period gross charge-offs
Total Loans			15,584
Commercial real estate | Construction and land | Pass
Term Loans Amortized Cost Basis by Origination Year
2024	813	813
2023	5,377	5,377
2022	10,501	10,501
2020	1,164	1,164
Prior	2,098	2,098
Total	19,953	19,953
Current period gross charge-offs
Total Loans			15,584
Commercial
Term Loans Amortized Cost Basis by Origination Year
2023	7,732	7,732
2022	6,441	6,441
2020	42	42
Prior	571	571
Total	14,786	14,786
Current period gross charge-offs
Total Loans			15,433
Commercial | Pass
Term Loans Amortized Cost Basis by Origination Year
2023	7,732	7,732
2022	6,441	6,441
2020	42	42
Prior	571	571
Total	14,786	14,786
Current period gross charge-offs
Total Loans			15,433
Consumer
Term Loans Amortized Cost Basis by Origination Year
2024	138	138
2023	116	116
2022	40	40
2020	5	5
Prior	1,698	1,698
Total	1,997	1,997
Current period gross charge-offs
Prior		13
Total	13	13
Total Loans			2,000
Consumer | Performing
Term Loans Amortized Cost Basis by Origination Year
2024	138	138
2023	116	116
2022	40	40
2020	5	5
Prior	1,587	1,587
Total	1,886	1,886
Current period gross charge-offs
Total Loans			1,918
Consumer | Nonperforming
Term Loans Amortized Cost Basis by Origination Year
Prior	111	111
Total	$ 111	$ 111
Current period gross charge-offs
Total Loans			$ 82