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Securities - Additional Information (Detail) - USD ($) | 6 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Jun. 30, 2024
Debt Securities, Available-for-sale [Line Items] |  |  |
Mortgage-backed securities with a book value | $ 211,193,000 |  | $ 219,523,000
Fair Value | $ 182,890,000 |  | 190,475,000
Percentage of equity securities | 10.00% |  |
Repurchase agreements | $ 18,439,000 |  | 17,772,000
Gross gains from sales of available for sale securities | 30,000 | $ 0 |
Gross losses from sales of available for sale securities | 101,000 | 0 |
Tax benefit to net realized gains (losses) | 20 | 0 |
Investments in debt and marketable equity securities | $ 181,142,000 |  | $ 185,652,000
Temporarily impaired debt securities percentage of investment securities portfolio | 99.00% |  | 97.00%
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Interest Receivable |  | Interest Receivable
Asset Pledged as Collateral with Right [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Carrying value of securities pledged as collateral | $ 71,977,000 |  | $ 118,577,000
Tax benefit to net realized gains (losses) | 20,000 | $ 0 |
Maturity Overnight [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Repurchase agreements | 18,400,000 |  |
Mortgage-backed securities – GSE residential [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Mortgage-backed securities with a book value | 188,708,000 |  | 192,556,000
Fair Value | 162,835,000 |  | 166,236,000
Investments in debt and marketable equity securities | 162,835,000 |  | 163,470,000
Small Business Administration [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Mortgage-backed securities with a book value | 15,720,000 |  | 16,387,000
Fair Value | 13,537,000 |  | 14,086,000
Investments in debt and marketable equity securities | 13,537,000 |  | 14,086,000
Debt Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Investments in debt and marketable equity securities | $ 181,142,000 |  | $ 185,652,000

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