EMPLOYEE BENEFIT PLANS - Significant Unobservable Inputs (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2019 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets at beginning of fiscal year	$ 150,634
Fair value of plan assets at end of fiscal year	145,319
Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets at beginning of fiscal year	0
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Purchase, Sale, and Settlement	7,695
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Actual Return (Loss) on Plan Assets Still Held	1,081
Fair value of plan assets at end of fiscal year	$ 8,776