Commitments and Contingencies - Purchase Obligations and Product Warranties (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Dec. 30, 2017	Dec. 31, 2016
Purchase Obligations
Legally-binding purchase commitment obligations	$ 187.4		$ 187.4
Typical duration of supply agreements with single or limited source vendors			1 year
Product Warranties
Product warranty term			12 months
Changes in warranty reserve
Balance as of beginning of period	9.4	$ 5.4	$ 9.7	$ 2.8
Provision for warranty	1.9	4.9	2.9	8.7
Utilization of reserve	(1.4)	(1.6)	(2.7)	(2.8)
Balance as of end of period	$ 9.9	$ 8.7	$ 9.9	$ 8.7
Minimum
Product Warranties
Product warranty term			6 months
Maximum
Product Warranties
Product warranty term			5 years

No definition available.

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- Definition

Represents the warranty period (in months) offered to general customers for most of the entity's products.

+ References

No definition available.

+ Details

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- Definition

The typical duration of supply agreements that the entity has with single or limited source vendors.

+ References

No definition available.

+ Details

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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

No definition available.

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- References

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

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- Definition

Amount of increase in the standard and extended product warranty accrual from warranties issued.

+ References

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- Definition

Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.7-03(a)(19))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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