Acquired Intangibles - Summary of Life, Gross Carrying Value of Acquired Intangible Assets, and Related Accumulated Amortization (Detail) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2015	Jun. 30, 2015
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 324.7	$ 330.6
Accumulated amortization	(104.0)	(95.2)
Acquired intangibles, net	$ 220.7	235.4
Weighted Average Life in Years	4 years 3 months 18 days
Display Driver Developed 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
Fingerprint Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 75.6	75.6
Weighted Average Life in Years	3 years 7 months 6 days
Thin Touch Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 8.9	8.9
Weighted Average Life in Years	7 years
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 48.4	48.4
Weighted Average Life in Years	2 years 9 months 18 days
Licensed Technology and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 1.3	1.3
Weighted Average Life in Years	5 years
Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross		10.3
Weighted Average Life in Years	0 years
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 4.5	0.1
Weighted Average Life in Years	7 years 10 months 24 days
Supplier Arrangement [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles, gross	$ 22.0	$ 22.0
Weighted Average Life in Years	1 year 9 months 18 days

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=26713463&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=26713463&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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