Loans - Classes of the loan portfolio summarized by aggregate rating (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Jun. 30, 2025
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025	$ 35,524	$ 44,288
2025/2024	42,164	9,118
2024/2023	5,985	20,099
2023/2022	13,024	53,733
2022/2021	48,085	42,709
Prior	66,252	30,803
Revolving Loans	2,698	1,821
Total	213,732	202,571
Commercial real estate
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025	10,166	27,952
2025/2024	27,727	4,203
2024/2023	2,034	4,698
2023/2022	3,889	25,549
2022/2021	22,246	18,297
Prior	24,596	11,029
Revolving Loans	161	139
Total	90,819	91,867
Commercial and industrial
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025	432	415
2025/2024	380	64
2024/2023	72	513
2023/2022	398	1,125
2022/2021	902	1,483
Prior	1,466	264
Revolving Loans	9	12
Total	3,659	3,876
Construction
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025		733
2025/2024	800
Total	800	733
Multi-family real estate
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025	12,629	5,444
2025/2024	3,627	1,617
2024/2023	1,241	8,190
2023/2022	2,547	16,275
2022/2021	15,569	13,043
Prior	16,034	3,193
Revolving Loans	32	46
Total	51,679	47,808
One-to-four-family residential
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025	12,297	9,565
2025/2024	9,474	3,196
2024/2023	2,606	6,667
2023/2022	6,165	10,699
2022/2021	9,310	9,886
Prior	24,156	16,317
Total	64,008	56,330
Consumer
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025		179
2025/2024	156	38
2024/2023	32	31
2023/2022	25	85
2022/2021	58
Revolving Loans	2,496	1,624
Total	2,767	1,957
Pass \| Commercial real estate
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025	10,166	27,952
2025/2024	27,727	4,203
2024/2023	2,034	4,041
2023/2022	3,236	25,549
2022/2021	22,246	18,297
Prior	24,596	11,029
Revolving Loans	161	139
Total	90,166	91,210
Pass \| Commercial and industrial
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025	432	415
2025/2024	380	64
2024/2023	72	513
2023/2022	398	1,125
2022/2021	902	1,483
Prior	1,466	264
Revolving Loans	9	12
Total	3,659	3,876
Pass \| Construction
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025		733
2025/2024	800
Total	800	733
Pass \| Multi-family real estate
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025	12,629	5,444
2025/2024	3,627	1,617
2024/2023	1,241	7,696
2023/2022	2,547	16,275
2022/2021	15,569	13,043
Prior	16,034	3,193
Revolving Loans	32	46
Total	51,679	47,314
Watch \| Commercial real estate
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2024/2023		657
2023/2022	653
Total	653	657
Watch \| Multi-family real estate
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2024/2023		494
Total		494
Performing \| One-to-four-family residential
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025	12,297	9,565
2025/2024	9,474	3,196
2024/2023	2,606	6,667
2023/2022	6,042	10,699
2022/2021	9,310	9,886
Prior	24,089	16,250
Total	63,818	56,263
Performing \| Consumer
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2026/2025		179
2025/2024	156	38
2024/2023	32	31
2023/2022	25	85
2022/2021	58
Revolving Loans	2,496	1,624
Total	2,767	1,957
Non-performing \| One-to-four-family residential
Loan portfolio summarized by the aggregate pass rating and the classified ratings of special mention, substandard and doubtful within the Company's internal risk rating system
2023/2022	123
Prior	67	67
Total	$ 190	$ 67

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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