Acquired Intangibles and Goodwill - Summary of Life, Gross Carrying Value and Related Accumulated Amortization of Acquired Intangible Assets (Detail) - USD ($) $ in Millions	6 Months Ended
Dec. 31, 2017	Jun. 30, 2017
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 459.7	$ 282.0
Accumulated amortization	(196.2)	(181.0)
Acquired intangibles, net	$ 263.5	101.0
Weighted Average Life in Years	4 years 9 months 18 days
Display Driver Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 164.0	164.0
Weighted Average Life in Years	5 years 3 months 18 days
Audio and Video Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 147.0
Weighted Average Life in Years	5 years
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 73.1	48.4
Weighted Average Life in Years	3 years 7 months 6 days
Fingerprint Authentication Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 55.7	63.5
Weighted Average Life in Years	4 years
Licensed Technology and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 9.0	1.3
Weighted Average Life in Years	4 years 3 months 19 days
Tradename [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 4.8
Weighted Average Life in Years	7 years
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 4.6	$ 4.8
Weighted Average Life in Years	7 years 8 months 12 days
Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 1.5
Weighted Average Life in Years	6 months

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

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

+ References

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- Definition

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+ References

No definition available.

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- Definition

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

+ References

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