Securities - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Jun. 30, 2024
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivable	$ 0		$ 0
Mortgage-backed securities with a book value	209,392		219,523
Fair Value	$ 184,585		190,475
Percentage of equity securities	10.00%
Repurchase agreements	$ 18,910		17,772
Gross gains from sales of available for sale securities	30		0
Gross losses from sales of available for sale securities	101	$ 0
Tax benefit to net realized gains (losses)	(20)	0
Investments in debt and marketable equity securities	$ 180,215		$ 185,652
Temporarily impaired debt securities percentage of investment securities portfolio	98.00%		97.00%
Asset Pledged as Collateral with Right [Member]
Debt Securities, Available-for-sale [Line Items]
Carrying value of securities pledged as collateral	$ 71,369		$ 118,577
Tax benefit to net realized gains (losses)	20	$ 0
Maturity Overnight [Member]
Debt Securities, Available-for-sale [Line Items]
Repurchase agreements	18,900
Mortgage-backed securities – GSE residential [Member]
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	189,455		192,556
Fair Value	166,731		166,236
Investments in debt and marketable equity securities	164,109		163,470
Small Business Administration [Member]
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	15,176		16,387
Fair Value	13,292		14,086
Investments in debt and marketable equity securities	13,292		14,086
Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Investments in debt and marketable equity securities	$ 180,215		$ 185,652

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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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 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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