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Loans and Allowance for Credit Losses on Loans - Financial Effect of Modifications Made to Borrowers Experiencing Financial Difficulty (Details) - Commercial Real Estate Portfolio [Member] | 3 Months Ended | 9 Months Ended
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Mar. 31, 2026 | Mar. 31, 2025 | Mar. 31, 2026 | Mar. 31, 2025
Term Extension [Member] |  |  |  |
Loans and Allowance for Credit Losses on Loans [Abstract] |  |  |  |
Weighted average life of loans | 6 months | 12 months |  | 12 months
Term Extension [Member] | Minimum [Member] |  |  |  |
Loans and Allowance for Credit Losses on Loans [Abstract] |  |  |  |
Weighted average life of loans |  |  | 6 months |
Term Extension [Member] | Maximum [Member] |  |  |  |
Loans and Allowance for Credit Losses on Loans [Abstract] |  |  |  |
Weighted average life of loans |  |  | 39 months |
Interest Rate Reduction [Member] |  |  |  |
Loans and Allowance for Credit Losses on Loans [Abstract] |  |  |  |
Weighted-average interest rate |  |  | 1.00% | 1.45%

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