INCOME TAXES (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 12,649	$ 6,258	$ 21,022	$ 14,664
Income before taxes from continuing operations	34,480	20,386	54,360	44,035
Restructuring charges	1,633		11,171
Restructuring charges, net of tax	1,224		8,377
Loss from debt extinguishment	1,235		7,925
Loss from debt extinguishment, net of tax	969		6,214
Other tax provisions (benefits)	$ 1,828	$ (669)	$ 1,248	$ (299)
Effective tax rate	30.80%	34.00%	32.60%	34.00%
Acquisition costs			$ 2,960
Acquisition costs, net of tax			$ 2,321

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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