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Securities - Amortized Cost and Fair Value of Available-for-Sale Securities by Contractual Maturity (Detail) - USD ($) | Sep. 30, 2025 | Jun. 30, 2025
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Within one year, Amortized Cost | $ 0 |
One to five years, Amortized Cost | 2,642,000 |
Five to ten years, Amortized Cost | 5,949,000 |
After ten years, Amortized Cost | 8,623,000 |
Amortized Cost | 17,214,000 |
Amortized Cost | 210,449,000 | $ 210,889,000
Within one year, Fair Value | 0 |
One to five years, Fair Value | 2,536,000 |
Five to ten years, Fair Value | 5,603,000 |
After ten years, Fair Value | 7,340,000 |
Fair Value | 15,479,000 |
Fair Value | 189,824,000 | 187,753,000
Mortgage-backed securities – GSE residential [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 193,235,000 | 192,261,000
Fair Value | $ 174,345,000 | $ 171,079,000

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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-3 + Details
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 320 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477268/942-320-50-3A + Details
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-3 + Details
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