INCOME TAXES - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Provision at statutory rate	$ 4,567	$ 3,072
Tax-exempt income	(294)	(1,201)
State income taxes	1,090	701
Interim period effective rate adjustment	860	5,263
Tax credit investments, net - federal	(4,800)	(9,568)
Research tax credit	(1,709)	0
IRC 162(m) nondeductible compensation	838	0
Other, net	128	42
Income tax expense (benefit)	$ 680	$ (1,691)
Effective tax rate	2.97%	(11.56%)

Effective Income Tax Rate Reconciliation, IRC 162(m) Nondeductible Compensation

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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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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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