Debt - Carrying Amounts of the Liability and Equity Components (Details) - USD ($) $ in Millions	Mar. 30, 2019	Jun. 30, 2018	May 29, 2018
Carrying amounts of the liability and equity components:
Current portion of long-term debt	$ 0.0	$ 275.3
Long-term debt, net of current portion	573.5	557.9
Convertible Notes
Carrying amounts of the liability and equity components:
Unamortized discount of liability component	(104.8)	(121.1)
Unamortized debt issuance cost	(6.7)	(7.7)
Carrying amount of liability component	573.5	833.2
Carrying amount of equity component	136.7	239.1
Convertible Notes \| 0.625% Senior Convertible Notes
Carrying amounts of the liability and equity components:
Principal amount of notes	$ 0.0	277.0
Interest rate on senior convertible notes	0.625%
Convertible Notes \| 1.00% Senior Convertible Notes
Carrying amounts of the liability and equity components:
Principal amount of notes	$ 460.0	460.0
Interest rate on senior convertible notes	1.00%
Convertible Notes \| 1.75% Senior Convertible Notes
Carrying amounts of the liability and equity components:
Principal amount of notes	$ 225.0	$ 225.0
Interest rate on senior convertible notes	1.75%		1.75%

The portion of the carrying value of long-term convertible debt as of the balance sheet date that is scheduled to be repaid within one year or in the normal operating cycle if longer. Convertible debt is a financial instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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- Definition

Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

+ References

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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-Publisher FASB
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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- References

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- Definition

Including the current and noncurrent portions, carrying amount of the debt liability component identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

+ References

No definition available.

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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion, net of the debt issuance costs allocated to the equity component.

+ References

No definition available.

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