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Loans and Allowance for Credit Losses - Credit Risk Profile of Association's Loan Portfolio Based on Risk Rating Category and Calendar Year of Origination (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Jun. 30, 2025
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | $ 67,913 | $ 45,850
2024 | 80,168 | 90,613
2023 | 117,527 | 119,598
2022 | 137,837 | 141,490
2021 | 75,145 | 76,629
Prior Years | 146,848 | 165,706
Total loans | 625,438 | 639,886
Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 67,913 | 45,850
2024 | 79,757 | 90,613
2023 | 114,171 | 116,226
2022 | 137,112 | 141,484
2021 | 74,211 | 75,395
Prior Years | 145,697 | 162,820
Total loans | 618,861 | 632,388
Watch [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2024 | 34 |
2023 | 274 |
2022 | 219 |
2021 |  | 186
Prior Years | 57 | 40
Total loans | 584 | 226
Substandard [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2024 | 377 |
2023 | 3,082 | 3,372
2022 | 506 | 6
2021 | 934 | 1,048
Prior Years | 1,094 | 2,846
Total loans | 5,993 | 7,272
One- to Four-Family [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 25,196 | 16,760
2024 | 24,115 | 23,826
2023 | 31,244 | 32,946
2022 | 43,954 | 45,176
2021 | 18,956 | 19,935
Prior Years | 38,152 | 40,336
Total loans | 181,617 | 178,979
Current period charge-offs Prior Years |  | (79)
Current period charge-offs Total |  | (79)
Current period recoveries Prior Years | 2 | 2
Current period recoveries Total | 2 | 2
One- to Four-Family [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 25,196 | 16,760
2024 | 23,827 | 23,826
2023 | 30,970 | 32,946
2022 | 43,951 | 45,173
2021 | 18,951 | 19,879
Prior Years | 37,950 | 40,102
Total loans | 180,845 | 178,686
One- to Four-Family [Member] | Watch [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2024 | 34 |
2023 | 274 |
2021 | 0 | 51
Prior Years | 40 | 40
Total loans | 348 | 91
One- to Four-Family [Member] | Substandard [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2024 | 254 |
2022 | 3 | 3
2021 | 5 | 5
Prior Years | 162 | 194
Total loans | 424 | 202
Multi-Family [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 7,326 | 4,517
2024 | 15,562 | 15,648
2023 | 10,322 | 10,379
2022 | 38,340 | 39,148
2021 | 19,684 | 19,827
Prior Years | 27,084 | 36,608
Total loans | 118,318 | 126,127
Current period charge-offs 2024 |  | (350)
Current period charge-offs Total |  | (350)
Current period recoveries 2024 |  | 220
Current period recoveries Total |  | 220
Multi-Family [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 7,326 | 4,517
2024 | 15,562 | 15,648
2023 | 10,322 | 10,379
2022 | 38,340 | 39,148
2021 | 19,684 | 19,827
Prior Years | 26,861 | 36,383
Total loans | 118,095 | 125,902
Multi-Family [Member] | Substandard [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Prior Years | 223 | 225
Total loans | 223 | 225
Home Equity Line of Credit [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 1,778 | 1,004
2024 | 2,570 | 2,884
2023 | 1,788 | 1,851
2022 | 1,512 | 1,616
2021 | 1,208 | 1,230
Prior Years | 1,503 | 1,902
Total loans | 10,359 | 10,487
Home Equity Line of Credit [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 1,778 | 1,004
2024 | 2,570 | 2,884
2023 | 1,788 | 1,851
2022 | 1,512 | 1,616
2021 | 1,208 | 1,230
Prior Years | 1,503 | 1,902
Total loans | 10,359 | 10,487
Construction [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 6,367 | 2,165
2024 | 1,476 | 8,574
2023 | 12,050 | 12,062
2022 | 122 | 123
Prior Years | 0 | 3
Total loans | 20,015 | 22,927
Construction [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 6,367 | 2,165
2024 | 1,476 | 8,574
2023 | 12,050 | 12,062
2022 | 122 | 123
Prior Years | 0 | 3
Total loans | 20,015 | 22,927
Commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 10,943 | 9,649
2024 | 14,322 | 14,724
2023 | 25,985 | 26,490
2022 | 49,836 | 50,471
2021 | 29,535 | 29,927
Prior Years | 65,401 | 70,289
Total loans | 196,022 | 201,550
Commercial [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 10,943 | 9,649
2024 | 14,199 | 14,724
2023 | 25,985 | 26,490
2022 | 49,163 | 50,471
2021 | 28,706 | 28,946
Prior Years | 64,903 | 69,788
Total loans | 193,899 | 200,068
Commercial [Member] | Watch [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2022 | 170 |
2021 | 0 | 135
Total loans | 170 | 135
Commercial [Member] | Substandard [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2024 | 123 |
2022 | 503 |
2021 | 829 | 846
Prior Years | 498 | 501
Total loans | 1,953 | 1,347
Commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 14,119 | 10,266
2024 | 20,747 | 23,374
2023 | 34,916 | 34,423
2022 | 3,298 | 4,073
2021 | 5,532 | 5,406
Prior Years | 14,631 | 16,419
Total loans | 93,243 | 93,961
Current period charge-offs 2025 |  | 0
Current period charge-offs 2024 | (70) | (50)
Current period charge-offs Total | (70) | (50)
Current period recoveries 2024 |  | 50
Current period recoveries Prior Years | 2 | 63
Current period recoveries Total | 2 | 113
Commercial [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 14,119 | 10,266
2024 | 20,747 | 23,374
2023 | 31,849 | 31,068
2022 | 3,249 | 4,070
2021 | 5,432 | 5,209
Prior Years | 14,403 | 14,493
Total loans | 89,799 | 88,480
Commercial [Member] | Watch [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2022 | 49 |
Prior Years | 17 |
Total loans | 66 |
Commercial [Member] | Substandard [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2024 |  | 0
2023 | 3,067 | 3,355
2022 |  | 3
2021 | 100 | 197
Prior Years | 211 | 1,926
Total loans | 3,378 | 5,481
Consumer [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 2,184 | 1,489
2024 | 1,376 | 1,583
2023 | 1,222 | 1,447
2022 | 775 | 883
2021 | 230 | 304
Prior Years | 77 | 149
Total loans | 5,864 | 5,855
Current period charge-offs 2025 | (9) | (28)
Current period charge-offs 2024 |  | (41)
Current period charge-offs 2022 |  | (1)
Current period charge-offs Total | (9) | (70)
Current period recoveries 2025 | 4 | 7
Current period recoveries 2024 |  | 13
Current period recoveries Total | 4 | 20
Consumer [Member] | Pass [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2025 | 2,184 | 1,489
2024 | 1,376 | 1,583
2023 | 1,207 | 1,430
2022 | 775 | 883
2021 | 230 | 304
Prior Years | 77 | 149
Total loans | 5,849 | 5,838
Consumer [Member] | Substandard [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
2023 | 15 | 17
Total loans | $ 15 | $ 17

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