The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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GOODWILL AND INTANGIBLE ASSETS Finite-lived Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Sep. 29, 2017
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	$ (43.6)		$ (43.6)		$ (31.2)
Total intangible assets with finite lives	71.9		71.9		87.3
Intangibles assets	75.9		75.9		91.3
Amortization of intangible assets	4.1	$ 3.4	12.5	$ 6.2
Impairment of intangible assets			3.0	$ 0.0
Developed technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	57.0		57.0		57.0
Patents, licenses and other
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	19.4		19.4		19.4
Customer contracts and supplier relationship
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	39.1		39.1		42.1
In Process Research and Development
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets Acquired			$ 4.0		$ 4.0
Production Relocation
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets	$ 3.0