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Securities - Amortized Cost and Approximate Fair Value of Securities, Together with Gross Unrealized Gains and Losses of Securities (Detail) - USD ($) $ in Thousands | Sep. 30, 2024 | Jun. 30, 2024
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 215,050 | $ 219,523
Gross Unrealized Gains | 65 | 41
Gross Unrealized Losses | (22,464) | (29,089)
Fair Value | 192,651 | 190,475
U.S. Treasury [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost |  | 497
Gross Unrealized Gains |  | 0
Gross Unrealized Losses |  | (53)
Fair Value |  | 444
U.S. Government and Federal Agency [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 5,983 | 6,979
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (220) | (370)
Fair Value | 5,763 | 6,609
Mortgage-backed: GSE residential [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 190,071 | 192,556
Gross Unrealized Gains | 62 | 41
Gross Unrealized Losses | (20,495) | (26,361)
Fair Value | 169,638 | 166,236
Small Business Administration [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 15,898 | 16,387
Gross Unrealized Gains | 3 | 0
Gross Unrealized Losses | (1,749) | (2,301)
Fair Value | 14,152 | 14,086
State and political subdivisions [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 3,098 | 3,104
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | (4)
Fair Value | $ 3,098 | $ 3,100

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- Definition Amount, before tax, of unrealized gain 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 (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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