INCOME TAXES - Schedule of Information LIHTC Portfolio Amounts (Details) - USD ($) $ in Thousands	12 Months Ended
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,

Amount, before amortization expense, of income tax credit and other tax benefit generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method.

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