INCOME TAXES (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Provision (benefit) from income taxes	$ 6,258	$ 1,560	$ 14,664	$ (22,107)
Income (loss) before taxes from continuing operations	20,386	9,002	44,035	10,117
Other tax provisions	$ (669)	1,430	$ (299)
Acquisition related costs		3,598		7,597
Acquisition related costs net of tax		$ 2,320		5,046
Special dividend ESOP charges				3,220
Special dividend ESOP charges, net of tax				2,125
Secondary equity offering costs				1,205
Secondary equity offering costs, net of tax				$ 795
Effective tax rate	34.00%	33.90%	34.00%	33.90%
Net tax benefits				$ 24,080
Life insurance amounts				2,614
Life insurance related costs, net of tax				$ 248

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