Securities - Additional Information (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2024 USD ($) Securities	Mar. 31, 2023 USD ($)	Mar. 31, 2024 USD ($) Securities	Mar. 31, 2023 USD ($)	Jun. 30, 2023 USD ($)
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivable	$ 531		$ 531
Mortgage-backed securities with a book value	225,425		225,425		$ 231,672
Fair Value	$ 195,257		$ 195,257		201,299
Percentage of equity securities	10.00%		10.00%
Repurchase agreements	$ 18,182		$ 18,182		10,787
Gross gains from sales of available for sale securities	0	$ 12	0	$ 12
Gross losses from sales of available for sale securities	0	0	0	183
Investments in debt and marketable equity securities	$ 190,402		$ 190,402		$ 194,818
Temporarily impaired debt securities percentage of investment securities portfolio	98.00%		98.00%		97.00%
Tax benefit to net realized gains (losses)	$ 0	4	$ 0	48
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions \| Securities	174		174
Number of available for sale debt securities \| Securities	178		178
Asset Pledged as Collateral with Right [Member]
Debt Securities, Available-for-sale [Line Items]
Carrying value of securities pledged as collateral	$ 83,514		$ 83,514		$ 138,022
Tax benefit to net realized gains (losses)	0	$ 4	0	$ 48
Maturity Overnight [Member]
Debt Securities, Available-for-sale [Line Items]
Repurchase agreements	18,200		18,200
Mortgage-backed securities – GSE residential [Member]
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	198,279		198,279		203,139
Fair Value	170,938		170,938		175,726
Investments in debt and marketable equity securities	168,141		168,141		172,930
Small Business Administration [Member]
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	16,560		16,560		17,629
Fair Value	14,201		14,201		15,233
Investments in debt and marketable equity securities	14,201		14,201		13,910
Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Investments in debt and marketable equity securities	$ 190,402		$ 190,402		$ 94,818

Debt securities greater than stated percentage of equity securities.

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Number of available for sale debt securities.

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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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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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