GOODWILL AND INTANGIBLE ASSETS - Gross Carrying Amount and Accumulated Amortization of Intangible Assets (Detail) - USD ($) $ in Millions	Jun. 30, 2017	Sep. 30, 2016
Finite Lived Intangible Assets [Line Items]
Finite lived intangible assets, gross	$ 138.7	$ 137.5
Accumulated Amortization	(73.3)	(62.2)
Net Carrying Amount	65.4	75.3
Indefinite intangible assets	8.8	8.8
Total intangible assets	147.5	146.3
Total intangible assets, net	74.2	84.1	[1]
Technologies and patents
Finite Lived Intangible Assets [Line Items]
Finite lived intangible assets, gross	99.3	99.6
Accumulated Amortization	(57.1)	(50.2)
Net Carrying Amount	42.2	49.4
Customer contracts and supplier relationship
Finite Lived Intangible Assets [Line Items]
Finite lived intangible assets, gross	33.9	32.3
Accumulated Amortization	(13.3)	(10.8)
Net Carrying Amount	20.6	21.5
Other
Finite Lived Intangible Assets [Line Items]
Finite lived intangible assets, gross	5.5	5.6
Accumulated Amortization	(2.9)	(1.2)
Net Carrying Amount	$ 2.6	$ 4.4

[1] The condensed consolidated balance sheet as of September 30, 2016 was derived from audited financial statements as of that date, but does not include all disclosures required by accounting principles generally accepted in the United States of America.