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Securities - Association's Investments Gross Unrealized Investment Losses and Fair Value of Association's Investments with Unrealized Losses (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Jun. 30, 2025
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Debt Securities, Available-for-Sale [Line Items] |  |
Less than 12 Months, Fair Value | $ 9,607 | $ 9,129
Less than 12 Months, Unrealized Losses | (85) | (113)
12 Months or More, Fair Value | 161,382 | 164,276
12 Months or More, Unrealized Losses | (20,761) | (23,093)
Total, Fair Value | 170,989 | 173,405
Total, Unrealized Losses | (20,846) | (23,206)
U.S. Government and federal agency |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Less than 12 Months, Fair Value | 0 | 0
Less than 12 Months, Unrealized Losses | 0 | 0
12 Months or More, Fair Value | 916 | 1,812
12 Months or More, Unrealized Losses | (77) | (174)
Total, Fair Value | 916 | 1,812
Total, Unrealized Losses | (77) | (174)
Mortgage-backed: GSE residential [Member] |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Less than 12 Months, Fair Value | 8,387 | 7,887
Less than 12 Months, Unrealized Losses | (68) | (100)
12 Months or More, Fair Value | 148,871 | 150,592
12 Months or More, Unrealized Losses | (19,043) | (21,152)
Total, Fair Value | 157,258 | 158,479
Total, Unrealized Losses | (19,111) | (21,252)
Small Business Administration [Member] |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Less than 12 Months, Fair Value | 1,220 | 1,242
Less than 12 Months, Unrealized Losses | (17) | (13)
12 Months or More, Fair Value | 11,595 | 11,872
12 Months or More, Unrealized Losses | (1,641) | (1,767)
Total, Fair Value | 12,815 | 13,114
Total, Unrealized Losses | $ (1,658) | $ (1,780)

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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479081/326-30-55-8 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-7 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-5 + Details
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