v3.26.1
LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES - Outstanding principal balance and carrying amount (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Sep. 30, 2025
LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES    
Balance $ 136,563 $ 132,835
Carrying Amount 135,297 131,504
Total Purchased Loans | Citizens Bank of Cape Vincent    
LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES    
Balance 24,063 26,372
Carrying Amount 23,434 25,658
Purchased Non-Credit Impaired Loans | Citizens Bank of Cape Vincent    
LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES    
Balance 24,063 26,372
Carrying Amount $ 23,434 $ 25,658