Goodwill and Intangible Assets, Net - Goodwill by Reportable Segment (Details) $ in Thousands	6 Months Ended
Sep. 30, 2018 USD ($)
Goodwill [Roll Forward]
Balance as of April 1, 2018	$ 420,117
Balance as of September 30, 2018	420,117
Communications
Goodwill [Roll Forward]
Balance as of April 1, 2018	141,300
Balance as of September 30, 2018	120,094
Computing, Consumer and Industrial
Goodwill [Roll Forward]
Balance as of April 1, 2018	278,817
Balance as of September 30, 2018	300,023
GigPeak, Inc.
Goodwill [Roll Forward]
Reallocation of goodwill	0
GigPeak, Inc. \| Communications
Goodwill [Roll Forward]
Reallocation of goodwill	(21,206)
GigPeak, Inc. \| Computing, Consumer and Industrial
Goodwill [Roll Forward]
Reallocation of goodwill	$ 21,206

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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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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