Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended		12 Months Ended
	Mar. 30, 2019	Dec. 29, 2018	Mar. 31, 2018	Mar. 30, 2019	Mar. 31, 2018	Sep. 29, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Other Tax Expense (Benefit)		$ 19.2	$ 327.0
Company's effective tax rate	22.90%		1.40%	30.20%	53.80%
Blended statutory income tax rate	21.00%						35.00%
Final Net Tax Benefit amount for Tax Cuts and Job Act		$ 341.2				$ 346.2
Provisional tax benefit of tax reform that relates to deferred taxes						$ 346.4
Benefit Reduction for Tax Cuts and Jobs Act	$ 5.0
Increase to income tax expense adoption of ASU 2016-16				$ 29.5
Decrease in deferred tax liabilities due to ASC 2016-16				48.7
Increase to Net Income resulted from adoption of ASU 2016-16				19.2
Increase to Earnings per Share resulted from adoption of ASC 2016-16	$ 0.0
Increase in deferred tax assets resulting from adoption of ASCU 2016-16				2.9
Decease in accumulated deficit resulting from adoption of ASCU 2016-16				2.5
Decease to prepaid taxes resulting from adoption of ASCU 2016-16				$ 0.4