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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 | Dec. 31, 2023 | Jun. 30, 2023
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 227,972 | $ 231,672
Gross Unrealized Gains | 77 | 22
Gross Unrealized Losses | (28,119) | (30,395)
Fair Value | 199,930 | 201,299
U.S. Treasury [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 496 | 497
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (49) | (59)
Fair Value | 447 | 438
U.S. Government and Federal Agency [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 6,978 | 6,976
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (394) | (499)
Fair Value | 6,584 | 6,477
Mortgage-backed: GSE residential [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 198,149 | 203,139
Gross Unrealized Gains | 76 | 21
Gross Unrealized Losses | (25,332) | (27,434)
Fair Value | 172,893 | 175,726
Small Business Administration [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 16,919 | 17,629
Gross Unrealized Gains | 0 | 1
Gross Unrealized Losses | (2,265) | (2,397)
Fair Value | 14,654 | 15,233
State and political subdivisions [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 5,430 | 3,431
Gross Unrealized Gains | 1 | 0
Gross Unrealized Losses | (79) | (6)
Fair Value | $ 5,352 | $ 3,425

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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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- 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). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (aa) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + Details
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