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INCOME TAXES - Schedule of Information LIHTC Portfolio Amounts (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Income Tax Disclosure [Abstract] |  |
LIHTC tax benefits | $ 19,135 | $ 19,156
Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, before Amortization, Statement of Income or Comprehensive Income [Extensible Enumeration] | Income tax expense | Income tax expense
Investment Program, Proportional Amortization Method Elected Income Tax Credit And Other Income Tax Benefit Before Amortization Statement Of Cash Flows Extensible Enumeration Not Disclosed Flag | LIHTC tax benefits as of September 30, | LIHTC tax benefits as of September 30,
LIHTC amortization expense | $ 16,093 | $ 16,434
Investment Program, Proportional Amortization Method, Applied, Amortization Expense, Statement of Income or Comprehensive Income [Extensible Enumeration] | Income tax expense | Income tax expense
Investment Program, Proportional Amortization Method, Applied, Income Tax Credit And Other Tax Benefit, Amortization, Statement Of Cash Flows, Extensible Enumeration, Not Disclosed Flag | LIHTC amortization expense for the year ended September 30, | LIHTC amortization expense for the year ended September 30,

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