Income Taxes - Acquisition and integration expenses information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 27, 2015	Oct. 02, 2016	Sep. 27, 2015	Sep. 28, 2014
Income Taxes
Effective tax rate (as a percent)		32.60%	51.20%	24.70%
Acquisition and integration expenses and debt pre-payment fees		$ 13.3
Income tax benefit on business combination acquisition and integration expenses and debt pre-payment fees		0.0
Business combination acquisition related expenses		6.4
Business combination integration costs and debt pre-payment fees		6.9
R&D credits		$ 2.0	$ 1.2
Impairment charge	$ 60.8		$ 60.8
Effective income tax rate excluding R&D credits, acquisition expenses and debt pre-payment fees (as a percent)		30.90%	32.50%
Decrease in income tax rate from developments in ongoing examinations		2.00%