Securities - Amortized Cost and Approximate Fair Value of Securities, Together with Gross Unrealized Gains and Losses of Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Jun. 30, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 210,889	$ 219,523
Gross Unrealized Gains	70	41
Gross Unrealized Losses	(23,206)	(29,089)
Fair Value	187,753	190,475
U.S. Treasury [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		497
Gross Unrealized Gains		0
Gross Unrealized Losses		(53)
Fair Value		444
U.S. Government and Federal Agency and Government sponsored enterprises (GSEs) [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,986	6,979
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(174)	(370)
Fair Value	1,812	6,609
Mortgage-backed: GSE residential [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	192,261	192,556
Gross Unrealized Gains	70	41
Gross Unrealized Losses	(21,252)	(26,361)
Fair Value	171,079	166,236
Small Business Administration [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	14,894	16,387
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1,780)	(2,301)
Fair Value	13,114	14,086
State and political subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,748	3,104
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(4)
Fair Value	$ 1,748	$ 3,100

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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Amount, before tax, of unrealized loss 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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