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Securities - Amortized Cost and Fair Value of Securities Available-for-Sale (Details) - USD ($) $ in Thousands | Mar. 31, 2026 | Jun. 30, 2025
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Securities [Abstract] |  |  |
Amortized cost, total securities available-for-sale | [1] | $ 385,480 | $ 373,966
Unrealized gains |  | 1,379 | 1,687
Unrealized losses |  | 16,658 | 19,591
Fair value |  | 370,201 | 356,062
Accrued interest receivable |  | 5,100 | 4,500
US Treasury Securities [Member] |  |  |
Securities [Abstract] |  |  |
Amortized cost, total securities available-for-sale | [1] | 5,836 | 10,815
Unrealized gains |  | 0 | 0
Unrealized losses |  | 47 | 362
Fair value |  | 5,789 | 10,453
U.S. Government Sponsored Enterprises [Member] |  |  |
Securities [Abstract] |  |  |
Amortized cost, total securities available-for-sale | [1] | 7,097 | 13,029
Unrealized gains |  | 0 | 0
Unrealized losses |  | 726 | 1,385
Fair value |  | 6,371 | 11,644
State and Political Subdivisions [Member] |  |  |
Securities [Abstract] |  |  |
Amortized cost, total securities available-for-sale | [1] | 214,530 | 208,450
Unrealized gains |  | 1,113 | 1,394
Unrealized losses |  | 0 | 0
Fair value |  | 215,643 | 209,844
Mortgage-backed Securities-Residential [Member] |  |  |
Securities [Abstract] |  |  |
Amortized cost, total securities available-for-sale | [1] | 53,539 | 34,382
Unrealized gains |  | 209 | 212
Unrealized losses |  | 2,869 | 3,007
Fair value |  | 50,879 | 31,587
Mortgage-backed Securities-Multi-family [Member] |  |  |
Securities [Abstract] |  |  |
Amortized cost, total securities available-for-sale | [1] | 88,524 | 88,874
Unrealized gains |  | 0 | 0
Unrealized losses |  | 12,620 | 14,277
Fair value |  | 75,904 | 74,597
Corporate Debt Securities [Member] |  |  |
Securities [Abstract] |  |  |
Amortized cost, total securities available-for-sale | [1] | 15,954 | 18,416
Unrealized gains |  | 57 | 81
Unrealized losses |  | 396 | 560
Fair value |  | $ 15,615 | $ 17,937
[1] | Amortized cost excludes accrued interest receivable of $5.1 million and $4.5 million at March 31, 2026 and June 30, 2025, respectively, which is included in accrued interest receivable in the consolidated statements of financial condition.

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