Restructuring - Restructuring Plan Activity (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 03, 2026	Sep. 27, 2025
Restructuring Reserve [Roll Forward]
Restructuring and related benefits	$ (0.8)	$ (0.3)
Fiscal 2026 Plan
Restructuring Reserve [Roll Forward]
Beginning of period balance	6.5
Restructuring and related benefits	(1.0)
Cash settlements	(2.5)
End of period balance	3.0
Network and Service Enablement \| Fiscal 2026 Plan
Restructuring Reserve [Roll Forward]
Beginning of period balance	5.4
Restructuring and related benefits	(0.9)
Cash settlements	(2.4)
End of period balance	2.1
Optical Security and Performance Products \| Fiscal 2026 Plan
Restructuring Reserve [Roll Forward]
Beginning of period balance	1.1
Restructuring and related benefits	(0.1)
Cash settlements	(0.1)
End of period balance	$ 0.9

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.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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