Amount for accounts payable to related parties.

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RELATED-PARTY TRANSACTIONS Equity Method Investment-(Details) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Oct. 31, 2013	Dec. 29, 2017 USD ($) member	Dec. 30, 2016 USD ($)	Sep. 28, 2018 USD ($)	Sep. 29, 2017 USD ($)
Related Party Transaction [Line Items]
Income (loss) from equity method investments		$ (0.7)	$ 0.1
Varian
Related Party Transaction [Line Items]
Purchases from related party		$ 0.4	0.4
dpiX Holding \| Varian
Related Party Transaction [Line Items]
Equity method investment, ownership percentage		40.00%
Number of consortium members \| member		4
Income (loss) from equity method investments		$ (0.7)	0.3
Equity method investments		47.8			$ 50.0
Purchases from related party		6.6	$ 8.4
Accounts payable, related parties		$ 3.3			$ 3.4
Percentage of manufacturing capacity	50.00%
Percentage of fixed costs	50.00%
Scenario, Forecast \| Fixed Cost Commitments \| dpiX Holding \| Varian
Related Party Transaction [Line Items]
Purchases from related party				$ 16.3