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INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Income Taxes [Line Items]
U.S. federal statutory rate	21.00%	24.50%	35.00%
Amount of foreign tax credit carryforwards	$ 20.1
Amount of foreign net operating loss carryforwards	16.9
Amount of state net operating loss carryforwards	0.5
Equity compensation	4.1
Accrued interest and penalties related to unrecognized tax benefits	2.1	$ 2.2
Unrecognized tax benefits related to discontinued operations	15.3	$ 14.3
Domestic
Income Taxes [Line Items]
Amount of net operating loss carryforwards	8.9
State
Income Taxes [Line Items]
Amount of net operating loss carryforwards	14.5
Foreign
Income Taxes [Line Items]
Amount of net operating loss carryforwards	62.0
Tax credit carryforwards	24.9
Foreign minimum tax credit carryforwards	$ 1.9

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