Commitments and Contingencies - Restructuring Costs (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 28, 2018	Sep. 29, 2017
Restructuring Cost and Reserve [Line Items]
September 29, 2017	$ 3.9
Restructuring Charges (Reversals)	0.0
Cash Payments	(3.9)
September 28, 2018	0.0	$ 3.9
2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
September 29, 2017	3.9
Restructuring Charges (Reversals)	0.0	13.2
Cash Payments	(3.9)
September 28, 2018	$ 0.0	$ 3.9

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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