POST EMPLOYMENT BENEFITS - Net periodic benefit costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Components of net periodic benefit expense:
Interest cost	$ 733	$ 381
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest Expense	Interest Expense
Expected return on assets	$ (798)	$ (744)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other income (expense)	Other income (expense)
Amortization of prior gain	$ (152)	$ 0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Amortization of Prior Service Cost (Credit), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other income (expense)	Other income (expense)
Net periodic benefit cost	$ (217)	$ (363)