Acquired Intangibles - Summary of Life, Gross Carrying Value of Acquired Intangible Assets, and Related Accumulated Amortization (Detail) - USD ($) $ in Millions	12 Months Ended
Jun. 29, 2019	Jun. 30, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 445.5	$ 456.1
Accumulated Amortization	(300.7)	(236.9)
Net Carrying Value	$ 144.8	219.2
Weighted Average Life in Years	4 years 4 months 24 days
Display Driver Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 164.0	164.0
Accumulated Amortization	(148.1)	(116.5)
Net Carrying Value	$ 15.9	47.5
Weighted Average Life in Years	5 years 3 months 18 days
Audio and Video Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 138.6	133.9
Accumulated Amortization	(49.4)	(22.8)
Net Carrying Value	$ 89.2	111.1
Weighted Average Life in Years	5 years 3 months 19 days
Fingerprint Authentication Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 47.2	55.7
Accumulated Amortization	$ (47.2)	(53.7)
Net Carrying Value		2.0
Weighted Average Life in Years	4 years 8 months 12 days
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 81.8	81.8
Accumulated Amortization	(49.9)	(38.5)
Net Carrying Value	$ 31.9	43.3
Weighted Average Life in Years	4 years 1 month 6 days
Licensed Technology and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 7.7	9.0
Accumulated Amortization	(3.6)	(3.0)
Net Carrying Value	$ 4.1	6.0
Weighted Average Life in Years	4 years 2 months 12 days
Tradename [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 1.8	1.9
Accumulated Amortization	(0.5)	(0.2)
Net Carrying Value	$ 1.3	1.7
Weighted Average Life in Years	7 years
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 4.4	4.6
Accumulated Amortization	(2.0)	(1.7)
Net Carrying Value	$ 2.4	2.9
Weighted Average Life in Years	8 years 1 month 6 days
Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		0.5
Accumulated Amortization		(0.5)
Weighted Average Life in Years	0 years
In-Process Research and Development [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		4.7
Net Carrying Value		$ 4.7

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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-Topic 350
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