POST EMPLOYMENT BENEFITS - Reconciliation of Projected Benefit Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Retirement Benefits [Abstract]
Accumulated benefit obligation:	$ 12,957	$ 12,812
Change in projected benefit obligation:
Projected benefit obligation, beginning of period	12,812	24,302
Interest cost	733	381
Benefits paid	(570)	(595)
Foreign currency translation adjustment	1,235	(3,370)
Actuarial gains	(1,253)	(7,906)
Projected benefit obligation at end of period	12,957	12,812
Change in fair value of plan assets:
Fair value of plan assets, beginning of period	14,385	21,269
Actual loss on plan assets	(427)	(3,948)
Employer contributions	1,226	1,059
Foreign currency translation adjustment	1,379	(3,400)
Benefits paid	(570)	(595)
Fair value of plan assets, end of period	15,993	14,385
Funded status	$ 3,036	$ 1,573