OTHER COMPREHENSIVE INCOME (LOSS) (Details) - Summary of Amounts Reclassified from Accumulated Other Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
OCI, Net of Tax [Abstract]
Pension amortization	$ (529)	$ (836)	$ (1,587)	$ (2,508)
Cash flow hedges	177	(88)	185	(910)
Removal of PPC translation adjustment	0	0	(14,866)	0
Total gain (loss)	(352)	(924)	13,464	(3,418)
Tax benefit (expense)	(106)	(277)	3,222	(1,025)
Amounts reclassified from accumulated other comprehensive income (loss)	$ (246)	$ (647)	$ 10,242	$ (2,393)