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Loans and Allowance for Credit Losses - Summary Of Amortized Cost Of Loans Modified And Experiencing Financial Difficulty (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
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Sep. 30, 2024 | Jun. 30, 2024
Financing Receivable, Modifications [Line Items] |  |
Payment Delay | $ 385 | $ 385
Total Class of Financing Receivable | 0.06% | 0.06%
One- to four-family [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Payment Delay | $ 0 | $ 0
Total Class of Financing Receivable | 0.00% | 0.00%
Multi-family [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Payment Delay | $ 0 | $ 0
Total Class of Financing Receivable | 0.00% | 0.00%
Commercial [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Payment Delay | $ 252 | $ 252
Total Class of Financing Receivable | 0.12% | 0.13%
Home equity lines of credit [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Payment Delay | $ 0 | $ 0
Total Class of Financing Receivable | 0.00% | 0.00%
Construction [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Payment Delay | $ 0 | $ 0
Total Class of Financing Receivable | 0.00% | 0.00%
Commercial business [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Payment Delay | $ 133 | $ 133
Total Class of Financing Receivable | 0.13% | 0.15%
Consumer [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Payment Delay | $ 0 | $ 0
Total Class of Financing Receivable | 0.00% | 0.00%

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- Definition Accumulated amortized cost excluding accrued interest, of financing receivable modified for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
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