INCOME TAXES (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Income Tax Disclosures [Line Items]
Deferred tax assets related to operating loss carryforwards in foreign jurisdictions	$ 44.1
Deferred tax assets related to domestic federal net operating loss carryforwards	2.6
Deferred tax assets related to state net operating loss carryforwards	0.4
Deferred tax assets related to state credits	14.0
Deferred tax assets related to credits in foreign jurisdictions	0.2
Capital loss carryforwards	3.6
Valuation allowance on deferred tax assets	26.9	$ 40.7
Net change in the valuation allowance	(13.8)
Undistributed earnings in our non-U.S. subsidiaries	310.0
Total gross unrecognized tax benefits	5.1	5.8	$ 4.1	$ 4.6
Unrecognized tax benefits that would impact effective tax rate, if recognized	3.6	3.3	2.7
Accrued interest and penalties related to unrecognized tax benefits	3.0	3.0	0.4
Income tax expense for interest and penalties	0.0	0.2	0.2
Income Tax Holiday [Line Items]
Impact of tax holidays	$ 4.1	$ 4.3	$ 4.0
Benefit of tax holidays on net income per share (diluted)	$ 0.06	$ 0.07	$ 0.07
Minimum [Member]
Income Tax Disclosures [Line Items]
Amount of reasonably possible decrease	$ 0.5
Maximum [Member]
Income Tax Disclosures [Line Items]
Amount of reasonably possible decrease	$ 1.5
Inland Revenue, Singapore (IRAS) [Member]
Income Tax Holiday [Line Items]
Income tax holiday, year of expiration	2018
Puerto Rico Tax Authority [Member]
Income Tax Holiday [Line Items]
Income tax holiday, year of expiration	2025
State and Local Jurisdiction [Member] | Earliest Tax Year [Member]
Income Tax Disclosures [Line Items]
Operating loss carryforwards, year of expiration	Jan. 01, 2017
Tax credit carryforwards, year of expiration	Jan. 01, 2017
State and Local Jurisdiction [Member] | Latest Tax Year [Member]
Income Tax Disclosures [Line Items]
Operating loss carryforwards, year of expiration	Dec. 31, 2035
Tax credit carryforwards, year of expiration	Dec. 31, 2025
Domestic Tax Authority [Member] | Earliest Tax Year [Member]
Income Tax Disclosures [Line Items]
Operating loss carryforwards, year of expiration	Jan. 01, 2019
Domestic Tax Authority [Member] | Latest Tax Year [Member]
Income Tax Disclosures [Line Items]
Operating loss carryforwards, year of expiration	Dec. 31, 2033
Foreign Tax Authority [Member]
Income Tax Disclosures [Line Items]
Operating loss carryforwards, year of expiration	Dec. 31, 2021
Tax credit carryforwards, year of expiration	Dec. 31, 2021