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Securities - Amortized Cost and Approximate Fair Value of Securities, Together with Gross Unrealized Gains and Losses of Securities (Detail) - USD ($)	Sep. 30, 2025	Jun. 30, 2025
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 210,449,000	$ 210,889,000
Gross Unrealized Gains	221,000	70,000
Gross Unrealized Losses	(20,846,000)	(23,206,000)
Fair Value	189,824,000	187,753,000
U.S. Government and federal agency
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	993,000	1,986,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(77,000)	(174,000)
Fair Value	916,000	1,812,000
Mortgage-backed: GSE residential [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	193,235,000	192,261,000
Gross Unrealized Gains	221,000	70,000
Gross Unrealized Losses	(19,111,000)	(21,252,000)
Fair Value	174,345,000	171,079,000
Small Business Administration [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	14,473,000	14,894,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1,658,000)	(1,780,000)
Fair Value	12,815,000	13,114,000
State and political subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,748,000	1,748,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 1,748,000	$ 1,748,000

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