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Restructuring and Related Charges (Details) $ in Millions	3 Months Ended			12 Months Ended
Restructuring and Related Charges (Details) $ in Millions	Sep. 29, 2018 USD ($) employee	Dec. 30, 2017 employee	Sep. 30, 2017 USD ($)	Jul. 01, 2017 employee	Jun. 30, 2018 USD ($)
Summary of various restructuring plans
Balance at the beginning of the period	$ 7.5
Charges (Benefits)	14.8		$ 1.5
Cash Settlements	(7.8)
Non-cash Settlements and Other Adjustments	0.1
Balance at the end of the period	14.6
Long-term restructuring accrual	3.2				$ 0.1
NSE, including AW Restructuring Plan
Summary of various restructuring plans
Balance at the beginning of the period	0.0
Charges (Benefits)	14.5
Cash Settlements	(2.0)
Non-cash Settlements and Other Adjustments	0.0
Balance at the end of the period	$ 12.5
Number of employees impacted (employee) \| employee	240
Trilithic Restructuring Plan
Summary of various restructuring plans
Balance at the beginning of the period	$ 2.9
Charges (Benefits)	0.0
Cash Settlements	(2.9)
Non-cash Settlements and Other Adjustments	0.0
Balance at the end of the period	0.0
Number of employees impacted (employee) \| employee		40
Focused NSE Restructuring Plan
Summary of various restructuring plans
Balance at the beginning of the period	1.9
Charges (Benefits)	0.4
Cash Settlements	(2.0)
Non-cash Settlements and Other Adjustments	0.1
Balance at the end of the period	0.4
Number of employees impacted (employee) \| employee				360
NE Lease Restructuring Plan
Summary of various restructuring plans
Balance at the beginning of the period	1.2
Charges (Benefits)	0.0
Cash Settlements	(0.3)
Non-cash Settlements and Other Adjustments	0.0
Balance at the end of the period	0.9
Contractual obligations under the operating lease, net of sublease income, fair value	0.9
Other Plans - prior to fiscal 2016
Summary of various restructuring plans
Balance at the beginning of the period	1.5
Charges (Benefits)	(0.1)
Cash Settlements	(0.6)
Non-cash Settlements and Other Adjustments	0.0
Balance at the end of the period	0.8
Other Plans - prior to fiscal 2017
Summary of various restructuring plans
Balance at the end of the period	0.8
Exit of workspace in Vancouver, Canada \| Focused NSE Restructuring Plan
Summary of various restructuring plans
Balance at the end of the period	$ 0.4