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BORROWED FUNDS - Summary of Borrowed Funds (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt	$ 15,000		$ 10,000
Total	14,693	$ 9,558
Discount on debt			$ 1,200
Federal Home Loans Bank of Dallas
Debt Instrument [Line Items]
Debt modification discount	$ (307)	$ (442)
Federal Home Loan Bank Borrowings at 2.05 Percentage | Federal Home Loans Bank of Dallas
Debt Instrument [Line Items]
Federal Home Loan Bank Borrowings interest percentage	2.05%
Long-term debt	$ 15,000
Federal Home Loan Bank Borrowings at 0.93 Percentage | Federal Home Loans Bank of Dallas
Debt Instrument [Line Items]
Federal Home Loan Bank Borrowings interest percentage		0.93%
Long-term debt		$ 10,000

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