Securities - Additional Information (Detail) - USD ($)	3 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Jun. 30, 2025
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivable	$ 483,000
Mortgage-backed securities with a book value	210,449,000		$ 210,889,000
Fair Value	$ 189,824,000		187,753,000
Percentage of equity securities	10.00%
Repurchase agreements	$ 18,130,000		18,795,000
Gross gains from sales of available for sale securities	0	$ 30,000
Gross losses from sales of available for sale securities	114,000	101,000
Tax benefit to net realized gains (losses)	(32,000)	(20,000)
Investments in debt and marketable equity securities	$ 170,989,000		$ 173,405,000
Temporarily impaired debt securities percentage of investment securities portfolio	90.00%		92.00%
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest Receivable
Asset Pledged as Collateral with Right [Member]
Debt Securities, Available-for-sale [Line Items]
Carrying value of securities pledged as collateral	$ 70,859,000		$ 102,268,000
Tax benefit to net realized gains (losses)	32,000	$ 20,000
Maturity Overnight [Member]
Debt Securities, Available-for-sale [Line Items]
Repurchase agreements	18,100,000
Mortgage-backed securities – GSE residential [Member]
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	193,235,000		192,261,000
Fair Value	174,345,000		171,079,000
Investments in debt and marketable equity securities	157,258,000		158,479,000
Small Business Administration [Member]
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	14,473,000		14,894,000
Fair Value	12,815,000		13,114,000
Investments in debt and marketable equity securities	12,815,000		13,114,000
Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Investments in debt and marketable equity securities	$ 170,989,000		$ 173,405,000

Debt securities greater than stated percentage of equity securities.

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Temporarily impaired debt securities percentage of investment securities portfolio.

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Amount of 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, after allowance for credit loss, of accrued interest 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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Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, 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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Amortized cost, after allowance for credit loss, of 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 of realized gain 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 of realized loss 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 of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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