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Investment Securities - Schedule of Amortized Cost and Fair Value of Securities Available-for-Sale and Securities Held-to-Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025
Agency mortgage-backed: residential [Member]
Available-for-sale Securities
Available-for-sale Securities, Amortized cost	$ 11,832	$ 9,950
Available-for-sale Securities, Gross unrealized gains	12
Available-for-sale Securities, Gross unrealized losses	117	193
Available-for-sale Securities, Estimated fair value	11,727	9,757
Held-to-maturity Securities
Held-to-maturity Securities, Amortized cost	161	171
Held-to-maturity Securities, Gross unrealized gains	2
Held-to-maturity Securities, Gross unrealized losses	4	4
Held-to-maturity Securities, Estimated fair value	159	167
Agency mortgage-backed securities [Member] | Less Than 12 Months [Member]
Available-for-sale Securities
Available-for-sale Securities, Amortized cost	1,031	2,000
Available-for-sale Securities, Gross unrealized losses	2	20
Available-for-sale Securities, Estimated fair value	1,029	1,980
Held-to-maturity Securities
Held-to-maturity Securities, Amortized cost
Held-to-maturity Securities, Gross unrealized losses
Held-to-maturity Securities, Estimated fair value
Agency mortgage-backed securities [Member] | 12 Months or More [Member]
Available-for-sale Securities
Available-for-sale Securities, Amortized cost	7,396	6,700
Available-for-sale Securities, Gross unrealized losses	115	173
Available-for-sale Securities, Estimated fair value	7,281	6,527
Held-to-maturity Securities
Held-to-maturity Securities, Amortized cost	98	108
Held-to-maturity Securities, Gross unrealized losses	4	5
Held-to-maturity Securities, Estimated fair value	94	103
Total Temporarily Impaired AFS Securities [Member]
Available-for-sale Securities
Available-for-sale Securities, Amortized cost	8,427	8,700
Available-for-sale Securities, Gross unrealized losses	117	193
Available-for-sale Securities, Estimated fair value	8,310	8,507
Total Temporarily Impaired HTM Securities [Member]
Held-to-maturity Securities
Held-to-maturity Securities, Amortized cost	98	108
Held-to-maturity Securities, Gross unrealized losses	4	5
Held-to-maturity Securities, Estimated fair value	$ 94	$ 103

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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